diff --git a/src/routes/inventory/purchaseorders.js b/src/routes/inventory/purchaseorders.js
index 4b0160d..0977cc8 100644
--- a/src/routes/inventory/purchaseorders.js
+++ b/src/routes/inventory/purchaseorders.js
@@ -13,6 +13,9 @@ import {
   listPurchaseOrdersByPropertiesRouteHandler,
   getPurchaseOrderStatsRouteHandler,
   getPurchaseOrderHistoryRouteHandler,
+  postPurchaseOrderRouteHandler,
+  acknowledgePurchaseOrderRouteHandler,
+  cancelPurchaseOrderRouteHandler,
 } from '../../services/inventory/purchaseorders.js';
 
 // list of purchase orders
@@ -29,7 +32,7 @@ router.get('/properties', isAuthenticated, (req, res) => {
   const filter = getFilter(req.query, allowedFilters, false);
   var masterFilter = {};
   if (req.query.masterFilter) {
-    masterFilter = JSON.parse(req.query.masterFilter);
+    masterFilter = getFilter(JSON.parse(req.query.masterFilter), allowedFilters, true);
   }
   listPurchaseOrdersByPropertiesRouteHandler(req, res, properties, filter, masterFilter);
 });
@@ -65,4 +68,16 @@ router.delete('/:id', isAuthenticated, async (req, res) => {
   deletePurchaseOrderRouteHandler(req, res);
 });
 
+router.post('/:id/post', isAuthenticated, async (req, res) => {
+  postPurchaseOrderRouteHandler(req, res);
+});
+
+router.post('/:id/acknowledge', isAuthenticated, async (req, res) => {
+  acknowledgePurchaseOrderRouteHandler(req, res);
+});
+
+router.post('/:id/cancel', isAuthenticated, async (req, res) => {
+  cancelPurchaseOrderRouteHandler(req, res);
+});
+
 export default router;
diff --git a/src/services/inventory/purchaseorders.js b/src/services/inventory/purchaseorders.js
index 437f27f..2432f9a 100644
--- a/src/services/inventory/purchaseorders.js
+++ b/src/services/inventory/purchaseorders.js
@@ -7,11 +7,15 @@ import {
   listObjects,
   getObject,
   editObject,
+  editObjects,
   newObject,
   listObjectsByProperties,
   getModelStats,
   getModelHistory,
+  checkStates,
 } from '../../database/database.js';
+import { orderItemModel } from '../../database/schemas/inventory/orderitem.schema.js';
+import { shipmentModel } from '../../database/schemas/inventory/shipment.schema.js';
 
 const logger = log4js.getLogger('Purchase Orders');
 logger.level = config.server.logLevel;
@@ -95,6 +99,20 @@ export const editPurchaseOrderRouteHandler = async (req, res) => {
 
   logger.trace(`Purchase Order with ID: ${id}`);
 
+  const checkStatesResult = await checkStates({ model: purchaseOrderModel, id, states: ['draft'] });
+
+  if (checkStatesResult.error) {
+    logger.error('Error checking purchase order states:', checkStatesResult.error);
+    res.status(checkStatesResult.code).send(checkStatesResult);
+    return;
+  }
+
+  if (checkStatesResult === false) {
+    logger.error('Purchase order is not in draft state.');
+    res.status(400).send({ error: 'Purchase order is not in draft state.', code: 400 });
+    return;
+  }
+
   const updateData = {
     updatedAt: new Date(),
     vendor: req.body.vendor,
@@ -118,10 +136,40 @@ export const editPurchaseOrderRouteHandler = async (req, res) => {
   res.send(result);
 };
 
+export const editMultiplePurchaseOrdersRouteHandler = async (req, res) => {
+  const updates = req.body.map((update) => ({
+    _id: update._id,
+    vendor: update.vendor,
+  }));
+
+  if (!Array.isArray(updates)) {
+    return res.status(400).send({ error: 'Body must be an array of updates.', code: 400 });
+  }
+
+  const result = await editObjects({
+    model: purchaseOrderModel,
+    updates,
+    user: req.user,
+  });
+
+  if (result.error) {
+    logger.error('Error editing purchase orders:', result.error);
+    res.status(result.code || 500).send(result);
+    return;
+  }
+
+  logger.debug(`Edited ${updates.length} purchase orders`);
+
+  res.send(result);
+};
+
 export const newPurchaseOrderRouteHandler = async (req, res) => {
   const newData = {
     updatedAt: new Date(),
     vendor: req.body.vendor,
+    totalAmount: 0,
+    totalAmountWithTax: 0,
+    totalTaxAmount: 0,
   };
   const result = await newObject({
     model: purchaseOrderModel,
@@ -180,3 +228,232 @@ export const getPurchaseOrderHistoryRouteHandler = async (req, res) => {
   logger.trace('Purchase order history:', result);
   res.send(result);
 };
+
+export const postPurchaseOrderRouteHandler = async (req, res) => {
+  const id = new mongoose.Types.ObjectId(req.params.id);
+
+  logger.trace(`Purchase Order with ID: ${id}`);
+
+  const checkStatesResult = await checkStates({ model: purchaseOrderModel, id, states: ['draft'] });
+
+  if (checkStatesResult.error) {
+    logger.error('Error checking purchase order states:', checkStatesResult.error);
+    res.status(checkStatesResult.code).send(checkStatesResult);
+    return;
+  }
+
+  if (checkStatesResult === false) {
+    logger.error('Purchase order is not in draft state.');
+    res.status(400).send({ error: 'Purchase order is not in draft state.', code: 400 });
+    return;
+  }
+
+  const orderItemsResult = await listObjects({
+    model: orderItemModel,
+    filter: { order: id, orderType: 'purchaseOrder' },
+    pagination: false,
+  });
+
+  const shipmentsResult = await listObjects({
+    model: shipmentModel,
+    filter: { order: id, orderType: 'purchaseOrder' },
+    pagination: false,
+  });
+
+  for (const orderItem of orderItemsResult) {
+    if (orderItem.state.type != 'draft') {
+      logger.warn(`Order item ${orderItem._id} is not in draft state.`);
+      return res
+        .status(400)
+        .send({ error: `Order item ${orderItem._reference} not in draft state.`, code: 400 });
+    }
+    if (!orderItem?.shipment || orderItem?.shipment == null) {
+      logger.warn(`Order item ${orderItem._id} does not have a shipment.`);
+      return res
+        .status(400)
+        .send({ error: `Order item ${orderItem._reference} does not have a shipment.`, code: 400 });
+    }
+  }
+
+  for (const shipment of shipmentsResult) {
+    if (shipment.state.type != 'draft') {
+      logger.warn(`Shipment ${shipment._id} is not in draft state.`);
+      return res
+        .status(400)
+        .send({ error: `Shipment ${shipment._reference} not in draft state.`, code: 400 });
+    }
+  }
+
+  for (const orderItem of orderItemsResult) {
+    await editObject({
+      model: orderItemModel,
+      id: orderItem._id,
+      updateData: {
+        state: { type: 'ordered' },
+        orderedAt: new Date(),
+      },
+      user: req.user,
+    });
+  }
+
+  for (const shipment of shipmentsResult) {
+    await editObject({
+      model: shipmentModel,
+      id: shipment._id,
+      updateData: {
+        state: { type: 'planned' },
+      },
+      user: req.user,
+    });
+  }
+
+  const updateData = {
+    updatedAt: new Date(),
+    state: { type: 'sent' },
+    postedAt: new Date(),
+  };
+  const result = await editObject({
+    model: purchaseOrderModel,
+    id,
+    updateData,
+    user: req.user,
+  });
+
+  if (result.error) {
+    logger.error('Error posting purchase order:', result.error);
+    res.status(result.code).send(result);
+    return;
+  }
+
+  logger.debug(`Posted purchase order with ID: ${id}`);
+  res.send(result);
+};
+
+export const acknowledgePurchaseOrderRouteHandler = async (req, res) => {
+  const id = new mongoose.Types.ObjectId(req.params.id);
+
+  logger.trace(`Purchase Order with ID: ${id}`);
+
+  const checkStatesResult = await checkStates({ model: purchaseOrderModel, id, states: ['sent'] });
+
+  if (checkStatesResult.error) {
+    logger.error('Error checking purchase order states:', checkStatesResult.error);
+    res.status(checkStatesResult.code).send(checkStatesResult);
+    return;
+  }
+
+  if (checkStatesResult === false) {
+    logger.error('Purchase order is not in sent state.');
+    res.status(400).send({ error: 'Purchase order is not in sent state.', code: 400 });
+    return;
+  }
+
+  const updateData = {
+    updatedAt: new Date(),
+    state: { type: 'acknowledged' },
+    acknowledgedAt: new Date(),
+  };
+  const result = await editObject({
+    model: purchaseOrderModel,
+    id,
+    updateData,
+    user: req.user,
+  });
+
+  if (result.error) {
+    logger.error('Error acknowledging purchase order:', result.error);
+    res.status(result.code).send(result);
+    return;
+  }
+
+  logger.debug(`Acknowledged purchase order with ID: ${id}`);
+  res.send(result);
+};
+
+export const cancelPurchaseOrderRouteHandler = async (req, res) => {
+  const id = new mongoose.Types.ObjectId(req.params.id);
+
+  logger.trace(`Purchase Order with ID: ${id}`);
+
+  const checkStatesResult = await checkStates({
+    model: purchaseOrderModel,
+    id,
+    states: ['sent', 'acknowledged', 'partiallyShipped', 'shipped', 'partiallyReceived'],
+  });
+
+  if (checkStatesResult.error) {
+    logger.error('Error checking purchase order states:', checkStatesResult.error);
+    res.status(checkStatesResult.code).send(checkStatesResult);
+    return;
+  }
+
+  if (checkStatesResult === false) {
+    logger.error('Purchase order is not in a cancellable state.');
+    res.status(400).send({
+      error: 'Purchase order is not in a cancellable state (must be draft, sent, or acknowledged).',
+      code: 400,
+    });
+    return;
+  }
+
+  const orderItemsResult = await listObjects({
+    model: orderItemModel,
+    filter: { order: id, orderType: 'purchaseOrder' },
+    pagination: false,
+  });
+
+  const shipmentsResult = await listObjects({
+    model: shipmentModel,
+    filter: { order: id, orderType: 'purchaseOrder' },
+    pagination: false,
+  });
+
+  const allowedOrderItemStates = ['ordered', 'shipped'];
+  const allowedShipmentStates = ['shipped', 'planned'];
+
+  for (const orderItem of orderItemsResult) {
+    if (allowedOrderItemStates.includes(orderItem.state.type)) {
+      await editObject({
+        model: orderItemModel,
+        id: orderItem._id,
+        updateData: {
+          state: { type: 'cancelled' },
+        },
+        user: req.user,
+      });
+    }
+  }
+
+  for (const shipment of shipmentsResult) {
+    if (allowedShipmentStates.includes(shipment.state.type)) {
+      await editObject({
+        model: shipmentModel,
+        id: shipment._id,
+        updateData: {
+          state: { type: 'cancelled' },
+        },
+        user: req.user,
+      });
+    }
+  }
+  const updateData = {
+    updatedAt: new Date(),
+    state: { type: 'cancelled' },
+    cancelledAt: new Date(),
+  };
+  const result = await editObject({
+    model: purchaseOrderModel,
+    id,
+    updateData,
+    user: req.user,
+  });
+
+  if (result.error) {
+    logger.error('Error cancelling purchase order:', result.error);
+    res.status(result.code).send(result);
+    return;
+  }
+
+  logger.debug(`Cancelled purchase order with ID: ${id}`);
+  res.send(result);
+};