diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -2817,6 +2817,8 @@
     'PhortuneAccountTransaction' => 'applications/phortune/storage/PhortuneAccountTransaction.php',
     'PhortuneAccountTransactionQuery' => 'applications/phortune/query/PhortuneAccountTransactionQuery.php',
     'PhortuneAccountViewController' => 'applications/phortune/controller/PhortuneAccountViewController.php',
+    'PhortuneAdHocCart' => 'applications/phortune/cart/PhortuneAdHocCart.php',
+    'PhortuneAdHocProduct' => 'applications/phortune/product/PhortuneAdHocProduct.php',
     'PhortuneCart' => 'applications/phortune/storage/PhortuneCart.php',
     'PhortuneCartAcceptController' => 'applications/phortune/controller/PhortuneCartAcceptController.php',
     'PhortuneCartCancelController' => 'applications/phortune/controller/PhortuneCartCancelController.php',
@@ -2856,6 +2858,7 @@
     'PhortuneMerchantEditController' => 'applications/phortune/controller/PhortuneMerchantEditController.php',
     'PhortuneMerchantEditor' => 'applications/phortune/editor/PhortuneMerchantEditor.php',
     'PhortuneMerchantHasMemberEdgeType' => 'applications/phortune/edge/PhortuneMerchantHasMemberEdgeType.php',
+    'PhortuneMerchantInvoiceCreateController' => 'applications/phortune/controller/PhortuneMerchantInvoiceCreateController.php',
     'PhortuneMerchantListController' => 'applications/phortune/controller/PhortuneMerchantListController.php',
     'PhortuneMerchantPHIDType' => 'applications/phortune/phid/PhortuneMerchantPHIDType.php',
     'PhortuneMerchantQuery' => 'applications/phortune/query/PhortuneMerchantQuery.php',
@@ -6265,6 +6268,8 @@
     'PhortuneAccountTransaction' => 'PhabricatorApplicationTransaction',
     'PhortuneAccountTransactionQuery' => 'PhabricatorApplicationTransactionQuery',
     'PhortuneAccountViewController' => 'PhortuneController',
+    'PhortuneAdHocCart' => 'PhortuneCartImplementation',
+    'PhortuneAdHocProduct' => 'PhortuneProductImplementation',
     'PhortuneCart' => array(
       'PhortuneDAO',
       'PhabricatorApplicationTransactionInterface',
@@ -6312,6 +6317,7 @@
     'PhortuneMerchantEditController' => 'PhortuneMerchantController',
     'PhortuneMerchantEditor' => 'PhabricatorApplicationTransactionEditor',
     'PhortuneMerchantHasMemberEdgeType' => 'PhabricatorEdgeType',
+    'PhortuneMerchantInvoiceCreateController' => 'PhortuneMerchantController',
     'PhortuneMerchantListController' => 'PhortuneMerchantController',
     'PhortuneMerchantPHIDType' => 'PhabricatorPHIDType',
     'PhortuneMerchantQuery' => 'PhabricatorCursorPagedPolicyAwareQuery',
diff --git a/src/applications/phortune/application/PhabricatorPhortuneApplication.php b/src/applications/phortune/application/PhabricatorPhortuneApplication.php
--- a/src/applications/phortune/application/PhabricatorPhortuneApplication.php
+++ b/src/applications/phortune/application/PhabricatorPhortuneApplication.php
@@ -84,19 +84,24 @@
           'edit/(?:(?P<id>\d+)/)?' => 'PhortuneMerchantEditController',
           'orders/(?P<merchantID>\d+)/(?:query/(?P<queryKey>[^/]+)/)?'
             => 'PhortuneCartListController',
-          '(?P<merchantID>\d+)/cart/(?P<id>\d+)/' => array(
-            '' => 'PhortuneCartViewController',
-            '(?P<action>cancel|refund)/' => 'PhortuneCartCancelController',
-            'update/' => 'PhortuneCartUpdateController',
-            'accept/' => 'PhortuneCartAcceptController',
-          ),
-          '(?P<merchantID>\d+)/subscription/' => array(
-            '(?:query/(?P<queryKey>[^/]+)/)?'
-              => 'PhortuneSubscriptionListController',
-            'view/(?P<id>\d+)/'
-              => 'PhortuneSubscriptionViewController',
-            'order/(?P<subscriptionID>\d+)/'
-              => 'PhortuneCartListController',
+          '(?P<merchantID>\d+)/' => array(
+            'cart/(?P<id>\d+)/' => array(
+              '' => 'PhortuneCartViewController',
+              '(?P<action>cancel|refund)/' => 'PhortuneCartCancelController',
+              'update/' => 'PhortuneCartUpdateController',
+              'accept/' => 'PhortuneCartAcceptController',
+            ),
+            'subscription/' => array(
+              '(?:query/(?P<queryKey>[^/]+)/)?'
+                => 'PhortuneSubscriptionListController',
+              'view/(?P<id>\d+)/'
+                => 'PhortuneSubscriptionViewController',
+              'order/(?P<subscriptionID>\d+)/'
+                => 'PhortuneCartListController',
+            ),
+            'invoice/' => array(
+              'new/' => 'PhortuneMerchantInvoiceCreateController',
+            ),
           ),
           '(?P<id>\d+)/' => 'PhortuneMerchantViewController',
         ),
diff --git a/src/applications/phortune/cart/PhortuneAdHocCart.php b/src/applications/phortune/cart/PhortuneAdHocCart.php
new file mode 100644
--- /dev/null
+++ b/src/applications/phortune/cart/PhortuneAdHocCart.php
@@ -0,0 +1,39 @@
+<?php
+
+final class PhortuneAdHocCart extends PhortuneCartImplementation {
+
+  public function loadImplementationsForCarts(
+    PhabricatorUser $viewer,
+    array $carts) {
+
+    $results = array();
+    foreach ($carts as $key => $cart) {
+      $results[$key] = new PhortuneAdHocCart();
+    }
+
+    return $results;
+  }
+
+  public function getName(PhortuneCart $cart) {
+    return $cart->getMetadataValue('adhoc.title');
+  }
+
+  public function getDescription(PhortuneCart $cart) {
+    return $cart->getMetadataValue('adhoc.description');
+  }
+
+  public function getCancelURI(PhortuneCart $cart) {
+    return null;
+  }
+
+  public function getDoneURI(PhortuneCart $cart) {
+    return null;
+  }
+
+  public function willCreateCart(
+    PhabricatorUser $viewer,
+    PhortuneCart $cart) {
+    return;
+  }
+
+}
diff --git a/src/applications/phortune/cart/PhortuneCartImplementation.php b/src/applications/phortune/cart/PhortuneCartImplementation.php
--- a/src/applications/phortune/cart/PhortuneCartImplementation.php
+++ b/src/applications/phortune/cart/PhortuneCartImplementation.php
@@ -16,6 +16,10 @@
   abstract public function getCancelURI(PhortuneCart $cart);
   abstract public function getDoneURI(PhortuneCart $cart);
 
+  public function getDescription(PhortuneCart $cart) {
+    return null;
+  }
+
   public function getDoneActionName(PhortuneCart $cart) {
     return pht('Return to Application');
   }
diff --git a/src/applications/phortune/controller/PhortuneCartCheckoutController.php b/src/applications/phortune/controller/PhortuneCartCheckoutController.php
--- a/src/applications/phortune/controller/PhortuneCartCheckoutController.php
+++ b/src/applications/phortune/controller/PhortuneCartCheckoutController.php
@@ -209,6 +209,8 @@
       ->appendChild($form)
       ->appendChild($provider_form);
 
+    $description_box = $this->renderCartDescription($cart);
+
     $crumbs = $this->buildApplicationCrumbs();
     $crumbs->addTextCrumb(pht('Checkout'));
     $crumbs->addTextCrumb($title);
@@ -217,6 +219,7 @@
       array(
         $crumbs,
         $cart_box,
+        $description_box,
         $payment_box,
       ),
       array(
diff --git a/src/applications/phortune/controller/PhortuneCartController.php b/src/applications/phortune/controller/PhortuneCartController.php
--- a/src/applications/phortune/controller/PhortuneCartController.php
+++ b/src/applications/phortune/controller/PhortuneCartController.php
@@ -42,4 +42,26 @@
     return $table;
   }
 
+  protected function renderCartDescription(PhortuneCart $cart) {
+    $description = $cart->getDescription();
+    if (!strlen($description)) {
+      return null;
+    }
+
+    $output = PhabricatorMarkupEngine::renderOneObject(
+      id(new PhabricatorMarkupOneOff())
+        ->setPreserveLinebreaks(true)
+        ->setContent($description),
+      'default',
+      $this->getViewer());
+
+    $box = id(new PHUIBoxView())
+      ->addMargin(PHUI::MARGIN_LARGE)
+      ->appendChild($output);
+
+    return id(new PHUIObjectBoxView())
+      ->setHeaderText(pht('Description'))
+      ->appendChild($box);
+  }
+
 }
diff --git a/src/applications/phortune/controller/PhortuneCartViewController.php b/src/applications/phortune/controller/PhortuneCartViewController.php
--- a/src/applications/phortune/controller/PhortuneCartViewController.php
+++ b/src/applications/phortune/controller/PhortuneCartViewController.php
@@ -15,11 +15,16 @@
 
     $authority = $this->loadMerchantAuthority();
 
-    $cart = id(new PhortuneCartQuery())
+    $query = id(new PhortuneCartQuery())
       ->setViewer($viewer)
       ->withIDs(array($this->id))
-      ->needPurchases(true)
-      ->executeOne();
+      ->needPurchases(true);
+
+    if ($authority) {
+      $query->withMerchantPHIDs(array($authority->getPHID()));
+    }
+
+    $cart = $query->executeOne();
     if (!$cart) {
       return new Aphront404Response();
     }
@@ -35,6 +40,31 @@
     $error_view = null;
     $resume_uri = null;
     switch ($cart->getStatus()) {
+      case PhortuneCart::STATUS_READY:
+        if ($authority && $request->getStr('invoice')) {
+          // We arrived here by following the ad-hoc invoice workflow, and
+          // are acting with merchant authority.
+
+          $checkout_uri = PhabricatorEnv::getURI($cart->getCheckoutURI());
+
+          $invoice_message = array(
+            pht(
+              'Manual invoices do not automatically notify recipients yet. '.
+              'Send the payer this checkout link:'),
+            ' ',
+            phutil_tag(
+              'a',
+              array(
+                'href' => $checkout_uri,
+              ),
+              $checkout_uri),
+          );
+
+          $error_view = id(new PHUIInfoView())
+            ->setSeverity(PHUIInfoView::SEVERITY_WARNING)
+            ->setErrors(array($invoice_message));
+        }
+        break;
       case PhortuneCart::STATUS_PURCHASING:
         if ($can_edit) {
           $resume_uri = $cart->getMetadataValue('provider.checkoutURI');
@@ -86,7 +116,6 @@
         $error_view = id(new PHUIInfoView())
           ->setSeverity(PHUIInfoView::SEVERITY_NOTICE)
           ->appendChild(pht('This purchase has been completed.'));
-
         break;
     }
 
@@ -126,6 +155,8 @@
       $cart_box->setInfoView($error_view);
     }
 
+    $description = $this->renderCartDescription($cart);
+
     $charges = id(new PhortuneChargeQuery())
       ->setViewer($viewer)
       ->withCartPHIDs(array($cart->getPHID()))
@@ -171,6 +202,7 @@
       array(
         $crumbs,
         $cart_box,
+        $description,
         $charges,
         $timeline,
       ),
diff --git a/src/applications/phortune/controller/PhortuneMerchantInvoiceCreateController.php b/src/applications/phortune/controller/PhortuneMerchantInvoiceCreateController.php
new file mode 100644
--- /dev/null
+++ b/src/applications/phortune/controller/PhortuneMerchantInvoiceCreateController.php
@@ -0,0 +1,245 @@
+<?php
+
+final class PhortuneMerchantInvoiceCreateController
+  extends PhortuneMerchantController {
+
+  public function handleRequest(AphrontRequest $request) {
+    $viewer = $request->getUser();
+
+    $merchant = $this->loadMerchantAuthority();
+    if (!$merchant) {
+      return new Aphront404Response();
+    }
+
+    $merchant_id = $merchant->getID();
+    $cancel_uri = $this->getApplicationURI("/merchant/{$merchant_id}/");
+
+    // Load the user to invoice, or prompt the viewer to select one.
+    $target_user = null;
+    $user_phid = head($request->getArr('userPHID'));
+    if (!$user_phid) {
+      $user_phid = $request->getStr('userPHID');
+    }
+    if ($user_phid) {
+      $target_user = id(new PhabricatorPeopleQuery())
+        ->setViewer($viewer)
+        ->withPHIDs(array($user_phid))
+        ->executeOne();
+    }
+
+    if (!$target_user) {
+      $form = id(new AphrontFormView())
+        ->setUser($viewer)
+        ->appendRemarkupInstructions(pht('Choose a user to invoice.'))
+        ->appendControl(
+          id(new AphrontFormTokenizerControl())
+            ->setLabel(pht('User'))
+            ->setDatasource(new PhabricatorPeopleDatasource())
+            ->setName('userPHID')
+            ->setLimit(1));
+
+      return $this->newDialog()
+        ->setTitle(pht('Choose User'))
+        ->appendForm($form)
+        ->addCancelButton($cancel_uri)
+        ->addSubmitButton(pht('Continue'));
+    }
+
+    // Load the account to invoice, or prompt the viewer to select one.
+    $target_account = null;
+    $account_phid = $request->getStr('accountPHID');
+    if ($account_phid) {
+      $target_account = id(new PhortuneAccountQuery())
+        ->setViewer($viewer)
+        ->withPHIDs(array($account_phid))
+        ->withMemberPHIDs(array($target_user->getPHID()))
+        ->executeOne();
+    }
+
+    if (!$target_account) {
+      $accounts = PhortuneAccountQuery::loadAccountsForUser(
+        $target_user,
+        PhabricatorContentSource::newFromRequest($request));
+
+      $form = id(new AphrontFormView())
+        ->setUser($viewer)
+        ->addHiddenInput('userPHID', $target_user->getPHID())
+        ->appendRemarkupInstructions(pht('Choose which account to invoice.'))
+        ->appendControl(
+          id(new AphrontFormMarkupControl())
+            ->setLabel(pht('User'))
+            ->setValue($viewer->renderHandle($target_user->getPHID())))
+        ->appendControl(
+          id(new AphrontFormSelectControl())
+            ->setLabel(pht('Account'))
+            ->setName('accountPHID')
+            ->setValue($account_phid)
+            ->setOptions(mpull($accounts, 'getName', 'getPHID')));
+
+      return $this->newDialog()
+        ->setTitle(pht('Choose Account'))
+        ->appendForm($form)
+        ->addCancelButton($cancel_uri)
+        ->addSubmitButton(pht('Continue'));
+    }
+
+
+    // Now we build the actual invoice.
+    $title = pht('New Invoice');
+
+    $crumbs = $this->buildApplicationCrumbs();
+    $crumbs->addTextCrumb($merchant->getName());
+
+    $v_title = $request->getStr('title');
+    $e_title = true;
+
+    $v_name = $request->getStr('name');
+    $e_name = true;
+
+    $v_cost = $request->getStr('cost');
+    $e_cost = true;
+
+    $v_desc = $request->getStr('description');
+
+    $v_quantity = 1;
+    $e_quantity = null;
+
+    $errors = array();
+    if ($request->isFormPost() && $request->getStr('invoice')) {
+      $v_quantity = $request->getStr('quantity');
+
+      $e_title = null;
+      $e_name = null;
+      $e_cost = null;
+      $e_quantity = null;
+
+      if (!strlen($v_title)) {
+        $e_title = pht('Required');
+        $errors[] = pht('You must title this invoice.');
+      }
+
+      if (!strlen($v_name)) {
+        $e_name = pht('Required');
+        $errors[] = pht('You must provide a name for this purchase.');
+      }
+
+      if (!strlen($v_cost)) {
+        $e_cost = pht('Required');
+        $errors[] = pht('You must provide a cost for this purchase.');
+      } else {
+        try {
+          $v_currency = PhortuneCurrency::newFromUserInput(
+            $viewer,
+            $v_cost);
+        } catch (Exception $ex) {
+          $errors[] = $ex->getMessage();
+          $e_cost = pht('Invalid');
+        }
+      }
+
+      if ((int)$v_quantity <= 0) {
+        $e_quantity = pht('Invalid');
+        $errors[] = pht('Quantity must be a positive integer.');
+      }
+
+      if (!$errors) {
+        $unique = Filesystem::readRandomCharacters(16);
+
+        $product = id(new PhortuneProductQuery())
+          ->setViewer($target_user)
+          ->withClassAndRef('PhortuneAdHocProduct', $unique)
+          ->executeOne();
+
+        $cart_implementation = new PhortuneAdHocCart();
+
+        $cart = $target_account->newCart(
+          $target_user,
+          $cart_implementation,
+          $merchant);
+
+        $cart
+          ->setMetadataValue('adhoc.title', $v_title)
+          ->setMetadataValue('adhoc.description', $v_desc);
+
+        $purchase = $cart->newPurchase($target_user, $product)
+          ->setBasePriceAsCurrency($v_currency)
+          ->setQuantity((int)$v_quantity)
+          ->setMetadataValue('adhoc.name', $v_name)
+          ->save();
+
+        // TODO: Actually mark these as invoices. Right now, there's no easy
+        // way to do that.
+
+        $cart->activateCart();
+        $cart_id = $cart->getID();
+
+        $uri = "/merchant/{$merchant_id}/cart/{$cart_id}/?invoice=true";
+        $uri = $this->getApplicationURI($uri);
+
+        return id(new AphrontRedirectResponse())->setURI($uri);
+      }
+    }
+
+    $form = id(new AphrontFormView())
+      ->setUser($viewer)
+      ->addHiddenInput('userPHID', $target_user->getPHID())
+      ->addHiddenInput('accountPHID', $target_account->getPHID())
+      ->addHiddenInput('invoice', true)
+      ->appendControl(
+        id(new AphrontFormMarkupControl())
+          ->setLabel(pht('User'))
+          ->setValue($viewer->renderHandle($target_user->getPHID())))
+      ->appendControl(
+        id(new AphrontFormMarkupControl())
+          ->setLabel(pht('Account'))
+          ->setValue($viewer->renderHandle($target_account->getPHID())))
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setLabel(pht('Invoice Title'))
+          ->setName('title')
+          ->setValue($v_title)
+          ->setError($e_title))
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setLabel(pht('Purchase Name'))
+          ->setName('name')
+          ->setValue($v_name)
+          ->setError($e_name))
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setLabel(pht('Purchase Cost'))
+          ->setName('cost')
+          ->setValue($v_cost)
+          ->setError($e_cost))
+      ->appendChild(
+        id(new AphrontFormTextControl())
+          ->setLabel(pht('Quantity'))
+          ->setName('quantity')
+          ->setValue($v_quantity)
+          ->setError($e_quantity))
+      ->appendChild(
+        id(new AphrontFormTextAreaControl())
+          ->setLabel(pht('Invoice Description'))
+          ->setName('description')
+          ->setValue($v_desc))
+      ->appendChild(
+        id(new AphrontFormSubmitControl())
+          ->addCancelButton($cancel_uri)
+          ->setValue(pht('Send Invoice')));
+
+    $box = id(new PHUIObjectBoxView())
+      ->setHeaderText(pht('New Invoice'))
+      ->setFormErrors($errors)
+      ->appendChild($form);
+
+    return $this->buildApplicationPage(
+      array(
+        $crumbs,
+        $box,
+      ),
+      array(
+        'title' => $title,
+      ));
+  }
+
+}
diff --git a/src/applications/phortune/controller/PhortuneMerchantViewController.php b/src/applications/phortune/controller/PhortuneMerchantViewController.php
--- a/src/applications/phortune/controller/PhortuneMerchantViewController.php
+++ b/src/applications/phortune/controller/PhortuneMerchantViewController.php
@@ -192,6 +192,15 @@
         ->setDisabled(!$can_edit)
         ->setWorkflow(!$can_edit));
 
+
+    $view->addAction(
+      id(new PhabricatorActionView())
+        ->setName(pht('New Invoice'))
+        ->setIcon('fa-fax')
+        ->setHref($this->getApplicationURI("merchant/{$id}/invoice/new/"))
+        ->setDisabled(!$can_edit)
+        ->setWorkflow(!$can_edit));
+
     return $view;
   }
 
diff --git a/src/applications/phortune/product/PhortuneAdHocProduct.php b/src/applications/phortune/product/PhortuneAdHocProduct.php
new file mode 100644
--- /dev/null
+++ b/src/applications/phortune/product/PhortuneAdHocProduct.php
@@ -0,0 +1,42 @@
+<?php
+
+final class PhortuneAdHocProduct extends PhortuneProductImplementation {
+
+  private $ref;
+
+  public function loadImplementationsForRefs(
+    PhabricatorUser $viewer,
+    array $refs) {
+
+    $results = array();
+    foreach ($refs as $key => $ref) {
+      $product = new PhortuneAdHocProduct();
+      $product->ref = $ref;
+      $results[$key] = $product;
+    }
+
+    return $results;
+  }
+
+  public function getRef() {
+    return $this->ref;
+  }
+
+  public function getName(PhortuneProduct $product) {
+    return pht('Ad-Hoc Product');
+  }
+
+  public function getPurchaseName(
+    PhortuneProduct $product,
+    PhortunePurchase $purchase) {
+
+    return coalesce(
+      $purchase->getMetadataValue('adhoc.name'),
+      $this->getName($product));
+  }
+
+  public function getPriceAsCurrency(PhortuneProduct $product) {
+    return PhortuneCurrency::newEmptyCurrency();
+  }
+
+}
diff --git a/src/applications/phortune/storage/PhortuneCart.php b/src/applications/phortune/storage/PhortuneCart.php
--- a/src/applications/phortune/storage/PhortuneCart.php
+++ b/src/applications/phortune/storage/PhortuneCart.php
@@ -453,6 +453,10 @@
     return $this->getImplementation()->getCancelURI($this);
   }
 
+  public function getDescription() {
+    return $this->getImplementation()->getDescription($this);
+  }
+
   public function getDetailURI(PhortuneMerchant $authority = null) {
     if ($authority) {
       $prefix = 'merchant/'.$authority->getID().'/';
diff --git a/src/applications/phortune/storage/PhortunePurchase.php b/src/applications/phortune/storage/PhortunePurchase.php
--- a/src/applications/phortune/storage/PhortunePurchase.php
+++ b/src/applications/phortune/storage/PhortunePurchase.php
@@ -92,7 +92,14 @@
   }
 
   public function getTotalPriceAsCurrency() {
-    return $this->getBasePriceAsCurrency();
+    $base = $this->getBasePriceAsCurrency();
+
+    $price = PhortuneCurrency::newEmptyCurrency();
+    for ($ii = 0; $ii < $this->getQuantity(); $ii++) {
+      $price = $price->add($base);
+    }
+
+    return $price;
   }
 
   public function getMetadataValue($key, $default = null) {