diff --git a/lib/data/models/invoice_model.dart b/lib/data/models/invoice_model.dart
index 4cd981d82..0f79663ac 100644
--- a/lib/data/models/invoice_model.dart
+++ b/lib/data/models/invoice_model.dart
@@ -209,7 +209,7 @@ abstract class InvoiceEntity extends Object
       invitations: client == null
           ? BuiltList<InvitationEntity>()
           : BuiltList(client.emailContacts
-              .map((contact) => InvitationEntity(contactId: contact.id))
+              .map((contact) => InvitationEntity(clientContactId: contact.id))
               .toList()),
       updatedAt: 0,
       archivedAt: 0,
@@ -275,7 +275,8 @@ abstract class InvoiceEntity extends Object
             (lineItem) => lineItem.typeId != InvoiceItemEntity.TYPE_UNPAID_FEE)
         .toList())
     ..invitations.replace(invitations
-        .map((invitation) => InvitationEntity(contactId: invitation.contactId))
+        .map((invitation) =>
+            InvitationEntity(clientContactId: invitation.clientContactId))
         .toList()));
 
   InvoiceEntity applyClient(AppState state, ClientEntity client) {
@@ -1193,7 +1194,7 @@ abstract class InvoiceEntity extends Object
 
   InvitationEntity getInvitationForContact(ContactEntity contact) {
     return invitations.firstWhere(
-        (invitation) => invitation.contactId == contact.id,
+        (invitation) => invitation.clientContactId == contact.id,
         orElse: () => null);
   }
 
@@ -1579,11 +1580,15 @@ abstract class InvoiceItemEntity
 abstract class InvitationEntity extends Object
     with BaseEntity, SelectableEntity
     implements Built<InvitationEntity, InvitationEntityBuilder> {
-  factory InvitationEntity({String contactId}) {
+  factory InvitationEntity({
+    String clientContactId,
+    String vendorContactId,
+  }) {
     return _$InvitationEntity._(
       id: BaseEntity.nextId,
       isChanged: false,
-      contactId: contactId ?? '',
+      clientContactId: clientContactId ?? '',
+      vendorContactId: vendorContactId ?? '',
       createdAt: 0,
       key: '',
       link: '',
@@ -1611,7 +1616,10 @@ abstract class InvitationEntity extends Object
   String get link;
 
   @BuiltValueField(wireName: 'client_contact_id')
-  String get contactId;
+  String get clientContactId;
+
+  @BuiltValueField(wireName: 'vendor_contact_id')
+  String get vendorContactId;
 
   @BuiltValueField(wireName: 'sent_date', compare: false)
   String get sentDate;
@@ -1662,6 +1670,11 @@ abstract class InvitationEntity extends Object
   @override
   FormatNumberType get listDisplayAmountType => FormatNumberType.money;
 
+  // ignore: unused_element
+  static void _initializeBuilder(InvitationEntityBuilder builder) => builder
+    ..clientContactId = ''
+    ..vendorContactId = '';
+
   static Serializer<InvitationEntity> get serializer =>
       _$invitationEntitySerializer;
 }
diff --git a/lib/data/models/invoice_model.g.dart b/lib/data/models/invoice_model.g.dart
index 54835f563..45e1c4c43 100644
--- a/lib/data/models/invoice_model.g.dart
+++ b/lib/data/models/invoice_model.g.dart
@@ -935,7 +935,10 @@ class _$InvitationEntitySerializer
       'link',
       serializers.serialize(object.link, specifiedType: const FullType(String)),
       'client_contact_id',
-      serializers.serialize(object.contactId,
+      serializers.serialize(object.clientContactId,
+          specifiedType: const FullType(String)),
+      'vendor_contact_id',
+      serializers.serialize(object.vendorContactId,
           specifiedType: const FullType(String)),
       'sent_date',
       serializers.serialize(object.sentDate,
@@ -1025,7 +1028,11 @@ class _$InvitationEntitySerializer
               specifiedType: const FullType(String)) as String;
           break;
         case 'client_contact_id':
-          result.contactId = serializers.deserialize(value,
+          result.clientContactId = serializers.deserialize(value,
+              specifiedType: const FullType(String)) as String;
+          break;
+        case 'vendor_contact_id':
+          result.vendorContactId = serializers.deserialize(value,
               specifiedType: const FullType(String)) as String;
           break;
         case 'sent_date':
@@ -2806,7 +2813,9 @@ class _$InvitationEntity extends InvitationEntity {
   @override
   final String link;
   @override
-  final String contactId;
+  final String clientContactId;
+  @override
+  final String vendorContactId;
   @override
   final String sentDate;
   @override
@@ -2841,7 +2850,8 @@ class _$InvitationEntity extends InvitationEntity {
   _$InvitationEntity._(
       {this.key,
       this.link,
-      this.contactId,
+      this.clientContactId,
+      this.vendorContactId,
       this.sentDate,
       this.viewedDate,
       this.openedDate,
@@ -2859,7 +2869,9 @@ class _$InvitationEntity extends InvitationEntity {
     BuiltValueNullFieldError.checkNotNull(key, 'InvitationEntity', 'key');
     BuiltValueNullFieldError.checkNotNull(link, 'InvitationEntity', 'link');
     BuiltValueNullFieldError.checkNotNull(
-        contactId, 'InvitationEntity', 'contactId');
+        clientContactId, 'InvitationEntity', 'clientContactId');
+    BuiltValueNullFieldError.checkNotNull(
+        vendorContactId, 'InvitationEntity', 'vendorContactId');
     BuiltValueNullFieldError.checkNotNull(
         sentDate, 'InvitationEntity', 'sentDate');
     BuiltValueNullFieldError.checkNotNull(
@@ -2889,7 +2901,8 @@ class _$InvitationEntity extends InvitationEntity {
     return other is InvitationEntity &&
         key == other.key &&
         link == other.link &&
-        contactId == other.contactId &&
+        clientContactId == other.clientContactId &&
+        vendorContactId == other.vendorContactId &&
         isChanged == other.isChanged &&
         createdAt == other.createdAt &&
         updatedAt == other.updatedAt &&
@@ -2914,9 +2927,11 @@ class _$InvitationEntity extends InvitationEntity {
                                 $jc(
                                     $jc(
                                         $jc(
-                                            $jc($jc(0, key.hashCode),
-                                                link.hashCode),
-                                            contactId.hashCode),
+                                            $jc(
+                                                $jc($jc(0, key.hashCode),
+                                                    link.hashCode),
+                                                clientContactId.hashCode),
+                                            vendorContactId.hashCode),
                                         isChanged.hashCode),
                                     createdAt.hashCode),
                                 updatedAt.hashCode),
@@ -2933,7 +2948,8 @@ class _$InvitationEntity extends InvitationEntity {
     return (newBuiltValueToStringHelper('InvitationEntity')
           ..add('key', key)
           ..add('link', link)
-          ..add('contactId', contactId)
+          ..add('clientContactId', clientContactId)
+          ..add('vendorContactId', vendorContactId)
           ..add('sentDate', sentDate)
           ..add('viewedDate', viewedDate)
           ..add('openedDate', openedDate)
@@ -2963,9 +2979,15 @@ class InvitationEntityBuilder
   String get link => _$this._link;
   set link(String link) => _$this._link = link;
 
-  String _contactId;
-  String get contactId => _$this._contactId;
-  set contactId(String contactId) => _$this._contactId = contactId;
+  String _clientContactId;
+  String get clientContactId => _$this._clientContactId;
+  set clientContactId(String clientContactId) =>
+      _$this._clientContactId = clientContactId;
+
+  String _vendorContactId;
+  String get vendorContactId => _$this._vendorContactId;
+  set vendorContactId(String vendorContactId) =>
+      _$this._vendorContactId = vendorContactId;
 
   String _sentDate;
   String get sentDate => _$this._sentDate;
@@ -3021,14 +3043,17 @@ class InvitationEntityBuilder
   String get id => _$this._id;
   set id(String id) => _$this._id = id;
 
-  InvitationEntityBuilder();
+  InvitationEntityBuilder() {
+    InvitationEntity._initializeBuilder(this);
+  }
 
   InvitationEntityBuilder get _$this {
     final $v = _$v;
     if ($v != null) {
       _key = $v.key;
       _link = $v.link;
-      _contactId = $v.contactId;
+      _clientContactId = $v.clientContactId;
+      _vendorContactId = $v.vendorContactId;
       _sentDate = $v.sentDate;
       _viewedDate = $v.viewedDate;
       _openedDate = $v.openedDate;
@@ -3066,8 +3091,10 @@ class InvitationEntityBuilder
                 key, 'InvitationEntity', 'key'),
             link: BuiltValueNullFieldError.checkNotNull(
                 link, 'InvitationEntity', 'link'),
-            contactId: BuiltValueNullFieldError.checkNotNull(
-                contactId, 'InvitationEntity', 'contactId'),
+            clientContactId: BuiltValueNullFieldError.checkNotNull(
+                clientContactId, 'InvitationEntity', 'clientContactId'),
+            vendorContactId: BuiltValueNullFieldError.checkNotNull(
+                vendorContactId, 'InvitationEntity', 'vendorContactId'),
             sentDate: BuiltValueNullFieldError.checkNotNull(
                 sentDate, 'InvitationEntity', 'sentDate'),
             viewedDate: BuiltValueNullFieldError.checkNotNull(
@@ -3078,10 +3105,9 @@ class InvitationEntityBuilder
             isChanged: isChanged,
             createdAt: BuiltValueNullFieldError.checkNotNull(
                 createdAt, 'InvitationEntity', 'createdAt'),
-            updatedAt: BuiltValueNullFieldError.checkNotNull(
-                updatedAt, 'InvitationEntity', 'updatedAt'),
-            archivedAt: BuiltValueNullFieldError.checkNotNull(
-                archivedAt, 'InvitationEntity', 'archivedAt'),
+            updatedAt:
+                BuiltValueNullFieldError.checkNotNull(updatedAt, 'InvitationEntity', 'updatedAt'),
+            archivedAt: BuiltValueNullFieldError.checkNotNull(archivedAt, 'InvitationEntity', 'archivedAt'),
             isDeleted: isDeleted,
             createdUserId: createdUserId,
             assignedUserId: assignedUserId,
diff --git a/lib/data/models/vendor_model.dart b/lib/data/models/vendor_model.dart
index 506a6a4e8..ec9b03e5a 100644
--- a/lib/data/models/vendor_model.dart
+++ b/lib/data/models/vendor_model.dart
@@ -438,6 +438,12 @@ abstract class VendorEntity extends Object
     }
   }
 
+  List<VendorContactEntity> get emailContacts {
+    //final list = contacts.where((contact) => contact.sendEmail).toList();
+    final list = contacts.where((contact) => true).toList();
+    return list.isEmpty ? [primaryContact] : list;
+  }
+
   VendorContactEntity get primaryContact =>
       contacts.firstWhere((contact) => contact.isPrimary,
           orElse: () => VendorContactEntity());
diff --git a/lib/redux/credit/credit_reducer.dart b/lib/redux/credit/credit_reducer.dart
index 76723945a..e60552cfc 100644
--- a/lib/redux/credit/credit_reducer.dart
+++ b/lib/redux/credit/credit_reducer.dart
@@ -118,7 +118,7 @@ final editingReducer = combineReducers<InvoiceEntity>([
       ..isChanged = true
       ..clientId = client?.id ?? ''
       ..invitations.replace((client?.emailContacts ?? <ContactEntity>[])
-          .map((contact) => InvitationEntity(contactId: contact.id))
+          .map((contact) => InvitationEntity(clientContactId: contact.id))
           .toList()));
   }),
   TypedReducer<InvoiceEntity, RestoreCreditsSuccess>((credits, action) {
@@ -137,8 +137,8 @@ final editingReducer = combineReducers<InvoiceEntity>([
   TypedReducer<InvoiceEntity, DiscardChanges>(_clearEditing),
   TypedReducer<InvoiceEntity, AddCreditContact>((invoice, action) {
     return invoice.rebuild((b) => b
-      ..invitations.add(
-          action.invitation ?? InvitationEntity(contactId: action.contact.id)));
+      ..invitations.add(action.invitation ??
+          InvitationEntity(clientContactId: action.contact.id)));
   }),
   TypedReducer<InvoiceEntity, RemoveCreditContact>((invoice, action) {
     return invoice.rebuild((b) => b..invitations.remove(action.invitation));
diff --git a/lib/redux/credit/credit_selectors.dart b/lib/redux/credit/credit_selectors.dart
index c4bd8a98a..ee525c254 100644
--- a/lib/redux/credit/credit_selectors.dart
+++ b/lib/redux/credit/credit_selectors.dart
@@ -8,8 +8,9 @@ import 'package:invoiceninja_flutter/redux/app/app_state.dart';
 import 'package:invoiceninja_flutter/redux/ui/list_ui_state.dart';
 
 ContactEntity creditContactSelector(InvoiceEntity credit, ClientEntity client) {
-  var contactIds =
-      credit.invitations.map((invitation) => invitation.contactId).toList();
+  var contactIds = credit.invitations
+      .map((invitation) => invitation.clientContactId)
+      .toList();
   if (contactIds.contains(client.primaryContact.id)) {
     contactIds = [client.primaryContact.id];
   }
diff --git a/lib/redux/invoice/invoice_reducer.dart b/lib/redux/invoice/invoice_reducer.dart
index e0f2248e7..68cf1b1bf 100644
--- a/lib/redux/invoice/invoice_reducer.dart
+++ b/lib/redux/invoice/invoice_reducer.dart
@@ -122,7 +122,7 @@ final editingReducer = combineReducers<InvoiceEntity>([
       ..isChanged = true
       ..clientId = client?.id ?? ''
       ..invitations.replace((client?.emailContacts ?? <ContactEntity>[])
-          .map((contact) => InvitationEntity(contactId: contact.id))
+          .map((contact) => InvitationEntity(clientContactId: contact.id))
           .toList()));
   }),
   TypedReducer<InvoiceEntity, RestoreInvoicesSuccess>((invoices, action) {
@@ -141,8 +141,8 @@ final editingReducer = combineReducers<InvoiceEntity>([
   TypedReducer<InvoiceEntity, DiscardChanges>(_clearEditing),
   TypedReducer<InvoiceEntity, AddInvoiceContact>((invoice, action) {
     return invoice.rebuild((b) => b
-      ..invitations.add(
-          action.invitation ?? InvitationEntity(contactId: action.contact.id)));
+      ..invitations.add(action.invitation ??
+          InvitationEntity(clientContactId: action.contact.id)));
   }),
   TypedReducer<InvoiceEntity, RemoveInvoiceContact>((invoice, action) {
     return invoice.rebuild((b) => b..invitations.remove(action.invitation));
diff --git a/lib/redux/invoice/invoice_selectors.dart b/lib/redux/invoice/invoice_selectors.dart
index c77afb751..3fe779c6f 100644
--- a/lib/redux/invoice/invoice_selectors.dart
+++ b/lib/redux/invoice/invoice_selectors.dart
@@ -20,8 +20,9 @@ InvoiceEntity invoiceQuoteSelector(
 
 ContactEntity invoiceContactSelector(
     InvoiceEntity invoice, ClientEntity client) {
-  var contactIds =
-      invoice.invitations.map((invitation) => invitation.contactId).toList();
+  var contactIds = invoice.invitations
+      .map((invitation) => invitation.clientContactId)
+      .toList();
   if (contactIds.contains(client.primaryContact.id)) {
     contactIds = [client.primaryContact.id];
   }
diff --git a/lib/redux/purchase_order/purchase_order_actions.dart b/lib/redux/purchase_order/purchase_order_actions.dart
index dc0a24238..7bf5d9d4d 100644
--- a/lib/redux/purchase_order/purchase_order_actions.dart
+++ b/lib/redux/purchase_order/purchase_order_actions.dart
@@ -29,11 +29,13 @@ class EditPurchaseOrder implements PersistUI, PersistPrefs {
   EditPurchaseOrder(
       {@required this.purchaseOrder,
       this.completer,
+      this.purchaseOrderItemIndex,
       this.cancelCompleter,
       this.force = false});
 
   final InvoiceEntity purchaseOrder;
   final Completer completer;
+  final int purchaseOrderItemIndex;
   final Completer cancelCompleter;
   final bool force;
 }
@@ -66,6 +68,12 @@ class UpdatePurchaseOrder implements PersistUI {
   final InvoiceEntity purchaseOrder;
 }
 
+class UpdatePurchaseOrderVendor implements PersistUI {
+  UpdatePurchaseOrderVendor({this.vendor});
+
+  final VendorEntity vendor;
+}
+
 class LoadPurchaseOrder {
   LoadPurchaseOrder({this.completer, this.purchaseOrderId});
 
@@ -237,9 +245,9 @@ class EmailPurchaseOrderRequest implements StartSaving {
 }
 
 class EmailPurchaseOrderSuccess implements StopSaving, PersistData {
-  EmailPurchaseOrderSuccess(this.quote);
+  EmailPurchaseOrderSuccess(this.purchaseOrder);
 
-  final InvoiceEntity quote;
+  final InvoiceEntity purchaseOrder;
 }
 
 class EmailPurchaseOrderFailure implements StopSaving {
@@ -248,6 +256,44 @@ class EmailPurchaseOrderFailure implements StopSaving {
   final dynamic error;
 }
 
+class MarkSentPurchaseOrdersRequest implements StartSaving {
+  MarkSentPurchaseOrdersRequest(this.completer, this.purchaseOrderIds);
+
+  final Completer completer;
+  final List<String> purchaseOrderIds;
+}
+
+class MarkSentPurchaseOrderSuccess implements StopSaving, PersistData {
+  MarkSentPurchaseOrderSuccess(this.purchaseOrders);
+
+  final List<InvoiceEntity> purchaseOrders;
+}
+
+class MarkSentPurchaseOrderFailure implements StopSaving {
+  MarkSentPurchaseOrderFailure(this.error);
+
+  final Object error;
+}
+
+class ApprovePurchaseOrders implements StartSaving {
+  ApprovePurchaseOrders(this.completer, this.purchaseOrderIds);
+
+  final List<String> purchaseOrderIds;
+  final Completer completer;
+}
+
+class ApprovePurchaseOrderSuccess implements StopSaving {
+  ApprovePurchaseOrderSuccess({this.purchaseOrders});
+
+  final List<InvoiceEntity> purchaseOrders;
+}
+
+class ApprovePurchaseOrderFailure implements StopSaving {
+  ApprovePurchaseOrderFailure(this.error);
+
+  final dynamic error;
+}
+
 class AddPurchaseOrderContact implements PersistUI {
   AddPurchaseOrderContact({this.contact, this.invitation});
 
@@ -314,6 +360,18 @@ class FilterPurchaseOrdersByState implements PersistUI {
   final EntityState state;
 }
 
+class FilterPurchaseOrdersByStatus implements PersistUI {
+  FilterPurchaseOrdersByStatus(this.status);
+
+  final EntityStatus status;
+}
+
+class FilterPurchaseOrderDropdown {
+  FilterPurchaseOrderDropdown(this.filter);
+
+  final String filter;
+}
+
 class FilterPurchaseOrdersByCustom1 implements PersistUI {
   FilterPurchaseOrdersByCustom1(this.value);
 
diff --git a/lib/redux/purchase_order/purchase_order_reducer.dart b/lib/redux/purchase_order/purchase_order_reducer.dart
index 347ffdedc..027fac3ef 100644
--- a/lib/redux/purchase_order/purchase_order_reducer.dart
+++ b/lib/redux/purchase_order/purchase_order_reducer.dart
@@ -1,21 +1,28 @@
-import 'package:redux/redux.dart';
+// Package imports:
 import 'package:built_collection/built_collection.dart';
-import 'package:invoiceninja_flutter/redux/app/app_actions.dart';
 import 'package:invoiceninja_flutter/data/models/models.dart';
+import 'package:redux/redux.dart';
+
+// Project imports:
+import 'package:invoiceninja_flutter/redux/app/app_actions.dart';
 import 'package:invoiceninja_flutter/redux/company/company_actions.dart';
-import 'package:invoiceninja_flutter/redux/ui/entity_ui_state.dart';
 import 'package:invoiceninja_flutter/redux/purchase_order/purchase_order_actions.dart';
-import 'package:invoiceninja_flutter/redux/ui/list_ui_state.dart';
 import 'package:invoiceninja_flutter/redux/purchase_order/purchase_order_state.dart';
+import 'package:invoiceninja_flutter/redux/ui/entity_ui_state.dart';
+import 'package:invoiceninja_flutter/redux/ui/list_ui_state.dart';
 
 EntityUIState purchaseOrderUIReducer(
     PurchaseOrderUIState state, dynamic action) {
   return state.rebuild((b) => b
-    ..listUIState.replace(purchaseOrderListReducer(state.listUIState, action))
-    ..editing.replace(editingReducer(state.editing, action))
-    ..selectedId = selectedIdReducer(state.selectedId, action)
-    ..forceSelected = forceSelectedReducer(state.forceSelected, action)
-    ..tabIndex = tabIndexReducer(state.tabIndex, action));
+        ..listUIState
+            .replace(purchaseOrderListReducer(state.listUIState, action))
+        ..editing.replace(editingReducer(state.editing, action))
+        ..editingItemIndex = editingItemReducer(state.editingItemIndex, action)
+        ..selectedId = selectedIdReducer(state.selectedId, action)
+        ..forceSelected = forceSelectedReducer(state.forceSelected, action)
+        ..tabIndex = tabIndexReducer(state.tabIndex, action)
+      //..historyActivityId = historyActivityIdReducer(state.historyActivityId, action)
+      );
 }
 
 final forceSelectedReducer = combineReducers<bool>([
@@ -42,6 +49,27 @@ final tabIndexReducer = combineReducers<int>([
   }),
 ]);
 
+final historyActivityIdReducer = combineReducers<String>([
+  TypedReducer<String, ShowPdfPurchaseOrder>(
+      (index, action) => action.activityId),
+]);
+
+final editingItemReducer = combineReducers<int>([
+  TypedReducer<int, EditPurchaseOrder>(
+      (index, action) => action.purchaseOrderItemIndex),
+  TypedReducer<int, EditPurchaseOrderItem>((index, action) => action.itemIndex),
+]);
+
+Reducer<String> dropdownFilterReducer = combineReducers([
+  TypedReducer<String, FilterPurchaseOrderDropdown>(
+      filterpurchaseOrderDropdownReducer),
+]);
+
+String filterpurchaseOrderDropdownReducer(
+    String dropdownFilter, FilterPurchaseOrderDropdown action) {
+  return action.filter;
+}
+
 Reducer<String> selectedIdReducer = combineReducers([
   TypedReducer<String, ArchivePurchaseOrdersSuccess>((completer, action) => ''),
   TypedReducer<String, DeletePurchaseOrdersSuccess>((completer, action) => ''),
@@ -50,15 +78,21 @@ Reducer<String> selectedIdReducer = combineReducers([
           ? action.entityId
           : selectedId),
   TypedReducer<String, ViewPurchaseOrder>(
-      (String selectedId, dynamic action) => action.purchaseOrderId),
+      (selectedId, action) => action.purchaseOrderId),
   TypedReducer<String, AddPurchaseOrderSuccess>(
-      (String selectedId, dynamic action) => action.purchaseOrder.id),
+      (selectedId, action) => action.purchaseOrder.id),
+  TypedReducer<String, ShowEmailPurchaseOrder>(
+      (selectedId, action) => action.purchaseOrder.id),
+  TypedReducer<String, ShowPdfPurchaseOrder>(
+      (selectedId, action) => action.purchaseOrder.id),
   TypedReducer<String, SelectCompany>(
       (selectedId, action) => action.clearSelection ? '' : selectedId),
   TypedReducer<String, ClearEntityFilter>((selectedId, action) => ''),
   TypedReducer<String, SortPurchaseOrders>((selectedId, action) => ''),
   TypedReducer<String, FilterPurchaseOrders>((selectedId, action) => ''),
   TypedReducer<String, FilterPurchaseOrdersByState>((selectedId, action) => ''),
+  TypedReducer<String, FilterPurchaseOrdersByStatus>(
+      (selectedId, action) => ''),
   TypedReducer<String, FilterPurchaseOrdersByCustom1>(
       (selectedId, action) => ''),
   TypedReducer<String, FilterPurchaseOrdersByCustom2>(
@@ -67,6 +101,8 @@ Reducer<String> selectedIdReducer = combineReducers([
       (selectedId, action) => ''),
   TypedReducer<String, FilterPurchaseOrdersByCustom4>(
       (selectedId, action) => ''),
+  TypedReducer<String, ClearEntitySelection>((selectedId, action) =>
+      action.entityType == EntityType.purchaseOrder ? '' : selectedId),
   TypedReducer<String, FilterByEntity>(
       (selectedId, action) => action.clearSelection
           ? ''
@@ -78,6 +114,32 @@ Reducer<String> selectedIdReducer = combineReducers([
 final editingReducer = combineReducers<InvoiceEntity>([
   TypedReducer<InvoiceEntity, SavePurchaseOrderSuccess>(_updateEditing),
   TypedReducer<InvoiceEntity, AddPurchaseOrderSuccess>(_updateEditing),
+  TypedReducer<InvoiceEntity, EditPurchaseOrder>(_updateEditing),
+  TypedReducer<InvoiceEntity, UpdatePurchaseOrder>((purchaseOrder, action) {
+    return action.purchaseOrder.rebuild((b) => b..isChanged = true);
+  }),
+  TypedReducer<InvoiceEntity, AddPurchaseOrderItem>((invoice, action) {
+    return invoice.rebuild((b) => b..isChanged = true);
+  }),
+  TypedReducer<InvoiceEntity, MovePurchaseOrderItem>((invoice, action) {
+    return invoice.moveLineItem(action.oldIndex, action.newIndex);
+  }),
+  TypedReducer<InvoiceEntity, DeletePurchaseOrderItem>((invoice, action) {
+    return invoice.rebuild((b) => b..isChanged = true);
+  }),
+  TypedReducer<InvoiceEntity, UpdatePurchaseOrderItem>((invoice, action) {
+    return invoice.rebuild((b) => b..isChanged = true);
+  }),
+  TypedReducer<InvoiceEntity, UpdatePurchaseOrderVendor>(
+      (purchaseOrder, action) {
+    final vendor = action.vendor;
+    return purchaseOrder.rebuild((b) => b
+      ..isChanged = true
+      ..vendorId = vendor?.id ?? ''
+      ..invitations.replace((vendor?.emailContacts ?? <VendorContactEntity>[])
+          .map((contact) => InvitationEntity(vendorContactId: contact.id))
+          .toList()));
+  }),
   TypedReducer<InvoiceEntity, RestorePurchaseOrdersSuccess>(
       (purchaseOrders, action) {
     return action.purchaseOrders[0];
@@ -90,11 +152,21 @@ final editingReducer = combineReducers<InvoiceEntity>([
       (purchaseOrders, action) {
     return action.purchaseOrders[0];
   }),
-  TypedReducer<InvoiceEntity, EditPurchaseOrder>(_updateEditing),
-  TypedReducer<InvoiceEntity, UpdatePurchaseOrder>((purchaseOrder, action) {
-    return action.purchaseOrder.rebuild((b) => b..isChanged = true);
-  }),
+  TypedReducer<InvoiceEntity, AddPurchaseOrderItem>(_addPurchaseOrderItem),
+  TypedReducer<InvoiceEntity, AddPurchaseOrderItems>(_addPurchaseOrderItems),
+  TypedReducer<InvoiceEntity, DeletePurchaseOrderItem>(
+      _removePurchaseOrderItem),
+  TypedReducer<InvoiceEntity, UpdatePurchaseOrderItem>(
+      _updatePurchaseOrderItem),
   TypedReducer<InvoiceEntity, DiscardChanges>(_clearEditing),
+  TypedReducer<InvoiceEntity, AddPurchaseOrderContact>((invoice, action) {
+    return invoice.rebuild((b) => b
+      ..invitations.add(action.invitation ??
+          InvitationEntity(clientContactId: action.contact.id)));
+  }),
+  TypedReducer<InvoiceEntity, RemovePurchaseOrderContact>((invoice, action) {
+    return invoice.rebuild((b) => b..invitations.remove(action.invitation));
+  }),
 ]);
 
 InvoiceEntity _clearEditing(InvoiceEntity purchaseOrder, dynamic action) {
@@ -105,15 +177,49 @@ InvoiceEntity _updateEditing(InvoiceEntity purchaseOrder, dynamic action) {
   return action.purchaseOrder;
 }
 
+InvoiceEntity _addPurchaseOrderItem(
+    InvoiceEntity purchaseOrder, AddPurchaseOrderItem action) {
+  return purchaseOrder.rebuild(
+      (b) => b..lineItems.add(action.purchaseOrderItem ?? InvoiceItemEntity()));
+}
+
+InvoiceEntity _addPurchaseOrderItems(
+    InvoiceEntity purchaseOrder, AddPurchaseOrderItems action) {
+  return purchaseOrder.rebuild((b) => b..lineItems.addAll(action.lineItems));
+}
+
+InvoiceEntity _removePurchaseOrderItem(
+    InvoiceEntity purchaseOrder, DeletePurchaseOrderItem action) {
+  if (purchaseOrder.lineItems.length <= action.index) {
+    return purchaseOrder;
+  }
+  return purchaseOrder.rebuild((b) => b..lineItems.removeAt(action.index));
+}
+
+InvoiceEntity _updatePurchaseOrderItem(
+    InvoiceEntity purchaseOrder, UpdatePurchaseOrderItem action) {
+  if (purchaseOrder.lineItems.length <= action.index) {
+    return purchaseOrder;
+  }
+  return purchaseOrder
+      .rebuild((b) => b..lineItems[action.index] = action.purchaseOrderItem);
+}
+
 final purchaseOrderListReducer = combineReducers<ListUIState>([
   TypedReducer<ListUIState, SortPurchaseOrders>(_sortPurchaseOrders),
   TypedReducer<ListUIState, FilterPurchaseOrdersByState>(
       _filterPurchaseOrdersByState),
+  TypedReducer<ListUIState, FilterPurchaseOrdersByStatus>(
+      _filterPurchaseOrdersByStatus),
   TypedReducer<ListUIState, FilterPurchaseOrders>(_filterPurchaseOrders),
   TypedReducer<ListUIState, FilterPurchaseOrdersByCustom1>(
       _filterPurchaseOrdersByCustom1),
   TypedReducer<ListUIState, FilterPurchaseOrdersByCustom2>(
       _filterPurchaseOrdersByCustom2),
+  TypedReducer<ListUIState, FilterPurchaseOrdersByCustom3>(
+      _filterPurchaseOrdersByCustom3),
+  TypedReducer<ListUIState, FilterPurchaseOrdersByCustom4>(
+      _filterPurchaseOrdersByCustom4),
   TypedReducer<ListUIState, StartPurchaseOrderMultiselect>(
       _startListMultiselect),
   TypedReducer<ListUIState, AddToPurchaseOrderMultiselect>(
@@ -155,6 +261,28 @@ ListUIState _filterPurchaseOrdersByCustom2(
   }
 }
 
+ListUIState _filterPurchaseOrdersByCustom3(
+    ListUIState purchaseOrderListState, FilterPurchaseOrdersByCustom3 action) {
+  if (purchaseOrderListState.custom3Filters.contains(action.value)) {
+    return purchaseOrderListState
+        .rebuild((b) => b..custom3Filters.remove(action.value));
+  } else {
+    return purchaseOrderListState
+        .rebuild((b) => b..custom3Filters.add(action.value));
+  }
+}
+
+ListUIState _filterPurchaseOrdersByCustom4(
+    ListUIState purchaseOrderListState, FilterPurchaseOrdersByCustom4 action) {
+  if (purchaseOrderListState.custom4Filters.contains(action.value)) {
+    return purchaseOrderListState
+        .rebuild((b) => b..custom4Filters.remove(action.value));
+  } else {
+    return purchaseOrderListState
+        .rebuild((b) => b..custom4Filters.add(action.value));
+  }
+}
+
 ListUIState _filterPurchaseOrdersByState(
     ListUIState purchaseOrderListState, FilterPurchaseOrdersByState action) {
   if (purchaseOrderListState.stateFilters.contains(action.state)) {
@@ -166,6 +294,17 @@ ListUIState _filterPurchaseOrdersByState(
   }
 }
 
+ListUIState _filterPurchaseOrdersByStatus(
+    ListUIState purchaseOrderListState, FilterPurchaseOrdersByStatus action) {
+  if (purchaseOrderListState.statusFilters.contains(action.status)) {
+    return purchaseOrderListState
+        .rebuild((b) => b..statusFilters.remove(action.status));
+  } else {
+    return purchaseOrderListState
+        .rebuild((b) => b..statusFilters.add(action.status));
+  }
+}
+
 ListUIState _filterPurchaseOrders(
     ListUIState purchaseOrderListState, FilterPurchaseOrders action) {
   return purchaseOrderListState.rebuild((b) => b
@@ -183,24 +322,25 @@ ListUIState _sortPurchaseOrders(
 }
 
 ListUIState _startListMultiselect(
-    ListUIState productListState, StartPurchaseOrderMultiselect action) {
-  return productListState.rebuild((b) => b..selectedIds = ListBuilder());
+    ListUIState purchaseOrderListState, StartPurchaseOrderMultiselect action) {
+  return purchaseOrderListState.rebuild((b) => b..selectedIds = ListBuilder());
 }
 
 ListUIState _addToListMultiselect(
-    ListUIState productListState, AddToPurchaseOrderMultiselect action) {
-  return productListState.rebuild((b) => b..selectedIds.add(action.entity.id));
+    ListUIState purchaseOrderListState, AddToPurchaseOrderMultiselect action) {
+  return purchaseOrderListState
+      .rebuild((b) => b..selectedIds.add(action.entity.id));
 }
 
-ListUIState _removeFromListMultiselect(
-    ListUIState productListState, RemoveFromPurchaseOrderMultiselect action) {
-  return productListState
+ListUIState _removeFromListMultiselect(ListUIState purchaseOrderListState,
+    RemoveFromPurchaseOrderMultiselect action) {
+  return purchaseOrderListState
       .rebuild((b) => b..selectedIds.remove(action.entity.id));
 }
 
 ListUIState _clearListMultiselect(
-    ListUIState productListState, ClearPurchaseOrderMultiselect action) {
-  return productListState.rebuild((b) => b..selectedIds = null);
+    ListUIState purchaseOrderListState, ClearPurchaseOrderMultiselect action) {
+  return purchaseOrderListState.rebuild((b) => b..selectedIds = null);
 }
 
 final purchaseOrdersReducer = combineReducers<PurchaseOrderState>([
@@ -210,16 +350,33 @@ final purchaseOrdersReducer = combineReducers<PurchaseOrderState>([
   TypedReducer<PurchaseOrderState, LoadPurchaseOrdersSuccess>(
       _setLoadedPurchaseOrders),
   TypedReducer<PurchaseOrderState, LoadPurchaseOrderSuccess>(
-      _setLoadedPurchaseOrder),
+      _updatePurchaseOrder),
   TypedReducer<PurchaseOrderState, LoadCompanySuccess>(_setLoadedCompany),
+  TypedReducer<PurchaseOrderState, MarkSentPurchaseOrderSuccess>(
+      _markSentPurchaseOrderSuccess),
+  TypedReducer<PurchaseOrderState, EmailPurchaseOrderSuccess>(
+      _emailPurchaseOrderSuccess),
   TypedReducer<PurchaseOrderState, ArchivePurchaseOrdersSuccess>(
       _archivePurchaseOrderSuccess),
   TypedReducer<PurchaseOrderState, DeletePurchaseOrdersSuccess>(
       _deletePurchaseOrderSuccess),
   TypedReducer<PurchaseOrderState, RestorePurchaseOrdersSuccess>(
       _restorePurchaseOrderSuccess),
+  TypedReducer<PurchaseOrderState, ApprovePurchaseOrderSuccess>(
+      _approvePurchaseOrderSuccess),
 ]);
 
+PurchaseOrderState _markSentPurchaseOrderSuccess(
+    PurchaseOrderState purchaseOrderState,
+    MarkSentPurchaseOrderSuccess action) {
+  final purchaseOrderMap = Map<String, InvoiceEntity>.fromIterable(
+    action.purchaseOrders,
+    key: (dynamic item) => item.id,
+    value: (dynamic item) => item,
+  );
+  return purchaseOrderState.rebuild((b) => b..map.addAll(purchaseOrderMap));
+}
+
 PurchaseOrderState _archivePurchaseOrderSuccess(
     PurchaseOrderState purchaseOrderState,
     ArchivePurchaseOrdersSuccess action) {
@@ -249,23 +406,36 @@ PurchaseOrderState _restorePurchaseOrderSuccess(
   });
 }
 
+PurchaseOrderState _emailPurchaseOrderSuccess(
+    PurchaseOrderState purchaseOrderState, EmailPurchaseOrderSuccess action) {
+  return purchaseOrderState
+      .rebuild((b) => b..map[action.purchaseOrder.id] = action.purchaseOrder);
+}
+
+PurchaseOrderState _approvePurchaseOrderSuccess(
+    PurchaseOrderState purchaseOrderState, ApprovePurchaseOrderSuccess action) {
+  final purchaseOrderMap = Map<String, InvoiceEntity>.fromIterable(
+    action.purchaseOrders,
+    key: (dynamic item) => item.id,
+    value: (dynamic item) => item,
+  );
+  return purchaseOrderState.rebuild((b) => b..map.addAll(purchaseOrderMap));
+}
+
 PurchaseOrderState _addPurchaseOrder(
     PurchaseOrderState purchaseOrderState, AddPurchaseOrderSuccess action) {
   return purchaseOrderState.rebuild((b) => b
     ..map[action.purchaseOrder.id] = action.purchaseOrder
+        .rebuild((b) => b..loadedAt = DateTime.now().millisecondsSinceEpoch)
     ..list.add(action.purchaseOrder.id));
 }
 
 PurchaseOrderState _updatePurchaseOrder(
-    PurchaseOrderState purchaseOrderState, SavePurchaseOrderSuccess action) {
-  return purchaseOrderState
-      .rebuild((b) => b..map[action.purchaseOrder.id] = action.purchaseOrder);
-}
-
-PurchaseOrderState _setLoadedPurchaseOrder(
-    PurchaseOrderState purchaseOrderState, LoadPurchaseOrderSuccess action) {
-  return purchaseOrderState
-      .rebuild((b) => b..map[action.purchaseOrder.id] = action.purchaseOrder);
+    PurchaseOrderState invoiceState, dynamic action) {
+  final InvoiceEntity purchaseOrder = action.purchaseOrder;
+  return invoiceState.rebuild((b) => b
+    ..map[purchaseOrder.id] = purchaseOrder
+        .rebuild((b) => b..loadedAt = DateTime.now().millisecondsSinceEpoch));
 }
 
 PurchaseOrderState _setLoadedPurchaseOrders(
diff --git a/lib/redux/quote/quote_reducer.dart b/lib/redux/quote/quote_reducer.dart
index 3ade679d2..550f6bf38 100644
--- a/lib/redux/quote/quote_reducer.dart
+++ b/lib/redux/quote/quote_reducer.dart
@@ -119,7 +119,7 @@ final editingReducer = combineReducers<InvoiceEntity>([
       ..isChanged = true
       ..clientId = client?.id ?? ''
       ..invitations.replace((client?.emailContacts ?? <ContactEntity>[])
-          .map((contact) => InvitationEntity(contactId: contact.id))
+          .map((contact) => InvitationEntity(clientContactId: contact.id))
           .toList()));
   }),
   TypedReducer<InvoiceEntity, RestoreQuotesSuccess>((quotes, action) {
@@ -138,8 +138,8 @@ final editingReducer = combineReducers<InvoiceEntity>([
   TypedReducer<InvoiceEntity, DiscardChanges>(_clearEditing),
   TypedReducer<InvoiceEntity, AddQuoteContact>((invoice, action) {
     return invoice.rebuild((b) => b
-      ..invitations.add(
-          action.invitation ?? InvitationEntity(contactId: action.contact.id)));
+      ..invitations.add(action.invitation ??
+          InvitationEntity(clientContactId: action.contact.id)));
   }),
   TypedReducer<InvoiceEntity, RemoveQuoteContact>((invoice, action) {
     return invoice.rebuild((b) => b..invitations.remove(action.invitation));
@@ -151,7 +151,7 @@ InvoiceEntity _clearEditing(InvoiceEntity quote, dynamic action) {
 }
 
 InvoiceEntity _updateEditing(InvoiceEntity quote, dynamic action) {
-  return action.quote;
+  return action.purchaseOrder;
 }
 
 InvoiceEntity _addQuoteItem(InvoiceEntity quote, AddQuoteItem action) {
@@ -367,7 +367,7 @@ QuoteState _addQuote(QuoteState quoteState, AddQuoteSuccess action) {
 }
 
 QuoteState _updateQuote(QuoteState invoiceState, dynamic action) {
-  final InvoiceEntity quote = action.quote;
+  final InvoiceEntity quote = action.purchaseOrder;
   return invoiceState.rebuild((b) => b
     ..map[quote.id] = quote
         .rebuild((b) => b..loadedAt = DateTime.now().millisecondsSinceEpoch));
diff --git a/lib/redux/quote/quote_selectors.dart b/lib/redux/quote/quote_selectors.dart
index aed73e74d..3a707ec36 100644
--- a/lib/redux/quote/quote_selectors.dart
+++ b/lib/redux/quote/quote_selectors.dart
@@ -13,8 +13,9 @@ ClientEntity quoteClientSelector(
 }
 
 ContactEntity quoteContactSelector(InvoiceEntity quote, ClientEntity client) {
-  var contactIds =
-      quote.invitations.map((invitation) => invitation.contactId).toList();
+  var contactIds = quote.invitations
+      .map((invitation) => invitation.clientContactId)
+      .toList();
   if (contactIds.contains(client.primaryContact.id)) {
     contactIds = [client.primaryContact.id];
   }
diff --git a/lib/redux/recurring_invoice/recurring_invoice_reducer.dart b/lib/redux/recurring_invoice/recurring_invoice_reducer.dart
index b5457da7e..a8202c09e 100644
--- a/lib/redux/recurring_invoice/recurring_invoice_reducer.dart
+++ b/lib/redux/recurring_invoice/recurring_invoice_reducer.dart
@@ -145,7 +145,7 @@ final editingReducer = combineReducers<InvoiceEntity>([
       ..isChanged = true
       ..clientId = client?.id ?? ''
       ..invitations.replace((client?.emailContacts ?? <ContactEntity>[])
-          .map((contact) => InvitationEntity(contactId: contact.id))
+          .map((contact) => InvitationEntity(clientContactId: contact.id))
           .toList()));
   }),
   TypedReducer<InvoiceEntity, RestoreRecurringInvoicesSuccess>(
@@ -172,8 +172,8 @@ final editingReducer = combineReducers<InvoiceEntity>([
   TypedReducer<InvoiceEntity, AddRecurringInvoiceContact>(
       (recurringInvoice, action) {
     return recurringInvoice.rebuild((b) => b
-      ..invitations.add(
-          action.invitation ?? InvitationEntity(contactId: action.contact.id)));
+      ..invitations.add(action.invitation ??
+          InvitationEntity(clientContactId: action.contact.id)));
   }),
   TypedReducer<InvoiceEntity, RemoveRecurringInvoiceContact>(
       (recurringInvoice, action) {
diff --git a/lib/ui/app/invoice/invoice_email_view.dart b/lib/ui/app/invoice/invoice_email_view.dart
index 0098e23c4..467f3723b 100644
--- a/lib/ui/app/invoice/invoice_email_view.dart
+++ b/lib/ui/app/invoice/invoice_email_view.dart
@@ -177,7 +177,7 @@ class _InvoiceEmailViewState extends State<InvoiceEmailView>
     final settings = getClientSettings(state, client);
     final contacts = invoice.invitations
         .map((invitation) => client.contacts.firstWhere(
-            (contact) => contact.id == invitation.contactId,
+            (contact) => contact.id == invitation.clientContactId,
             orElse: () => null))
         .toList();
 
diff --git a/lib/ui/invoice/edit/invoice_edit_desktop.dart b/lib/ui/invoice/edit/invoice_edit_desktop.dart
index 66382dc9e..c5834b149 100644
--- a/lib/ui/invoice/edit/invoice_edit_desktop.dart
+++ b/lib/ui/invoice/edit/invoice_edit_desktop.dart
@@ -43,6 +43,7 @@ import 'package:invoiceninja_flutter/ui/invoice/edit/invoice_edit_contacts_vm.da
 import 'package:invoiceninja_flutter/ui/invoice/edit/invoice_edit_details_vm.dart';
 import 'package:invoiceninja_flutter/ui/invoice/edit/invoice_edit_items_vm.dart';
 import 'package:invoiceninja_flutter/ui/invoice/edit/invoice_edit_vm.dart';
+import 'package:invoiceninja_flutter/ui/purchase_order/edit/purchase_order_edit_items_vm.dart';
 import 'package:invoiceninja_flutter/ui/quote/edit/quote_edit_items_vm.dart';
 import 'package:invoiceninja_flutter/ui/recurring_invoice/edit/recurring_invoice_edit_items_vm.dart';
 import 'package:invoiceninja_flutter/utils/completers.dart';
@@ -568,6 +569,10 @@ class InvoiceEditDesktopState extends State<InvoiceEditDesktop>
               viewModel: widget.entityViewModel,
               isTasks: _showTasksTable,
             )
+          else if (entityType == EntityType.purchaseOrder)
+            PurchaseOrderEditItemsScreen(
+              viewModel: widget.entityViewModel,
+            )
           else
             SizedBox(),
           Row(
diff --git a/lib/ui/invoice/edit/invoice_edit_vm.dart b/lib/ui/invoice/edit/invoice_edit_vm.dart
index 5105884dd..44c65b477 100644
--- a/lib/ui/invoice/edit/invoice_edit_vm.dart
+++ b/lib/ui/invoice/edit/invoice_edit_vm.dart
@@ -203,7 +203,7 @@ class InvoiceEditVM extends AbstractInvoiceEditVM {
             ..projectId = projectId ?? ''
             ..invitations.replace(BuiltList<InvitationEntity>(client
                 .emailContacts
-                .map((contact) => InvitationEntity(contactId: contact.id))
+                .map((contact) => InvitationEntity(clientContactId: contact.id))
                 .toList())))));
         }
         store.dispatch(AddInvoiceItems(items));
diff --git a/lib/ui/invoice/view/invoice_view_contacts.dart b/lib/ui/invoice/view/invoice_view_contacts.dart
index 88ab6eeeb..83212c5c9 100644
--- a/lib/ui/invoice/view/invoice_view_contacts.dart
+++ b/lib/ui/invoice/view/invoice_view_contacts.dart
@@ -46,7 +46,7 @@ class _InvitationListTile extends StatelessWidget {
     final state = viewModel.state;
     final client = state.clientState.get(viewModel.invoice.clientId);
     final contact = client.contacts.firstWhere(
-        (contact) => contact.id == invitation.contactId,
+        (contact) => contact.id == invitation.clientContactId,
         orElse: () => ContactEntity());
 
     if (contact.isNew) {
diff --git a/lib/ui/reports/credit_report.dart b/lib/ui/reports/credit_report.dart
index c66f8319b..4f0c8596d 100644
--- a/lib/ui/reports/credit_report.dart
+++ b/lib/ui/reports/credit_report.dart
@@ -132,7 +132,7 @@ ReportResult creditReport(
       continue;
     }
 
-    final contact = client.getContact(credit.invitations.first.contactId);
+    final contact = client.getContact(credit.invitations.first.clientContactId);
 
     if (credit.isDeleted || client.isDeleted) {
       continue;
diff --git a/lib/ui/reports/invoice_report.dart b/lib/ui/reports/invoice_report.dart
index 1d80a8df1..41189da57 100644
--- a/lib/ui/reports/invoice_report.dart
+++ b/lib/ui/reports/invoice_report.dart
@@ -160,7 +160,8 @@ ReportResult invoiceReport(
       continue;
     }
 
-    final contact = client.getContact(invoice.invitations.first.contactId);
+    final contact =
+        client.getContact(invoice.invitations.first.clientContactId);
 
     if (invoice.isDeleted || client.isDeleted) {
       continue;
diff --git a/lib/ui/reports/quote_report.dart b/lib/ui/reports/quote_report.dart
index eb517b6d5..cce2126b4 100644
--- a/lib/ui/reports/quote_report.dart
+++ b/lib/ui/reports/quote_report.dart
@@ -130,7 +130,7 @@ ReportResult quoteReport(
       continue;
     }
 
-    final contact = client.getContact(quote.invitations.first.contactId);
+    final contact = client.getContact(quote.invitations.first.clientContactId);
     //final vendor = vendorMap[quote.vendorId];
 
     if (quote.isDeleted || client.isDeleted) {
diff --git a/lib/ui/reports/recurring_invoice_report.dart b/lib/ui/reports/recurring_invoice_report.dart
index 00c005c40..421a23423 100644
--- a/lib/ui/reports/recurring_invoice_report.dart
+++ b/lib/ui/reports/recurring_invoice_report.dart
@@ -152,7 +152,8 @@ ReportResult recurringInvoiceReport(
       continue;
     }
 
-    final contact = client.getContact(invoice.invitations.first.contactId);
+    final contact =
+        client.getContact(invoice.invitations.first.clientContactId);
 
     if (invoice.isDeleted || client.isDeleted) {
       continue;