diff --git a/resources/celerity/map.php b/resources/celerity/map.php
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -7,7 +7,7 @@
  */
 return array(
   'names' => array(
-    'core.pkg.css' => 'a419cf4b',
+    'core.pkg.css' => '3ea6dc33',
     'core.pkg.js' => '57dff7df',
     'darkconsole.pkg.js' => 'e7393ebb',
     'differential.pkg.css' => '2de124c9',
@@ -114,7 +114,7 @@
     'rsrc/css/font/phui-font-icon-base.css' => 'ecbbb4c2',
     'rsrc/css/layout/phabricator-filetree-view.css' => 'fccf9f82',
     'rsrc/css/layout/phabricator-hovercard-view.css' => '1239cd52',
-    'rsrc/css/layout/phabricator-side-menu-view.css' => 'bec2458e',
+    'rsrc/css/layout/phabricator-side-menu-view.css' => '91b7a42c',
     'rsrc/css/layout/phabricator-source-code-view.css' => 'cbeef983',
     'rsrc/css/phui/calendar/phui-calendar-day.css' => 'd1cf6f93',
     'rsrc/css/phui/calendar/phui-calendar-list.css' => 'c1c7f338',
@@ -762,7 +762,7 @@
     'phabricator-remarkup-css' => '7afb543c',
     'phabricator-search-results-css' => '7dea472c',
     'phabricator-shaped-request' => '7cbe244b',
-    'phabricator-side-menu-view-css' => 'bec2458e',
+    'phabricator-side-menu-view-css' => '91b7a42c',
     'phabricator-slowvote-css' => 'da0afb1b',
     'phabricator-source-code-view-css' => 'cbeef983',
     'phabricator-standard-page-view' => '3c99cdf4',
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
@@ -2855,6 +2855,7 @@
     'PhabricatorProjectIconSet' => 'applications/project/icon/PhabricatorProjectIconSet.php',
     'PhabricatorProjectInterface' => 'applications/project/interface/PhabricatorProjectInterface.php',
     'PhabricatorProjectListController' => 'applications/project/controller/PhabricatorProjectListController.php',
+    'PhabricatorProjectListView' => 'applications/project/view/PhabricatorProjectListView.php',
     'PhabricatorProjectLockController' => 'applications/project/controller/PhabricatorProjectLockController.php',
     'PhabricatorProjectLogicalAndDatasource' => 'applications/project/typeahead/PhabricatorProjectLogicalAndDatasource.php',
     'PhabricatorProjectLogicalDatasource' => 'applications/project/typeahead/PhabricatorProjectLogicalDatasource.php',
@@ -7206,6 +7207,7 @@
     'PhabricatorProjectHeraldAction' => 'HeraldAction',
     'PhabricatorProjectIconSet' => 'PhabricatorIconSet',
     'PhabricatorProjectListController' => 'PhabricatorProjectController',
+    'PhabricatorProjectListView' => 'AphrontView',
     'PhabricatorProjectLockController' => 'PhabricatorProjectController',
     'PhabricatorProjectLogicalAndDatasource' => 'PhabricatorTypeaheadCompositeDatasource',
     'PhabricatorProjectLogicalDatasource' => 'PhabricatorTypeaheadCompositeDatasource',
diff --git a/src/applications/project/__tests__/PhabricatorProjectCoreTestCase.php b/src/applications/project/__tests__/PhabricatorProjectCoreTestCase.php
--- a/src/applications/project/__tests__/PhabricatorProjectCoreTestCase.php
+++ b/src/applications/project/__tests__/PhabricatorProjectCoreTestCase.php
@@ -748,15 +748,15 @@
       ->setNewValue($name);
 
     if ($parent) {
-      $xactions[] = id(new PhabricatorProjectTransaction())
-        ->setTransactionType(PhabricatorProjectTransaction::TYPE_PARENT)
-        ->setNewValue($parent->getPHID());
-    }
-
-    if ($is_milestone) {
-      $xactions[] = id(new PhabricatorProjectTransaction())
-        ->setTransactionType(PhabricatorProjectTransaction::TYPE_MILESTONE)
-        ->setNewValue(true);
+      if ($is_milestone) {
+        $xactions[] = id(new PhabricatorProjectTransaction())
+          ->setTransactionType(PhabricatorProjectTransaction::TYPE_MILESTONE)
+          ->setNewValue($parent->getPHID());
+      } else {
+        $xactions[] = id(new PhabricatorProjectTransaction())
+          ->setTransactionType(PhabricatorProjectTransaction::TYPE_PARENT)
+          ->setNewValue($parent->getPHID());
+      }
     }
 
     $this->applyTransactions($project, $user, $xactions);
diff --git a/src/applications/project/controller/PhabricatorProjectController.php b/src/applications/project/controller/PhabricatorProjectController.php
--- a/src/applications/project/controller/PhabricatorProjectController.php
+++ b/src/applications/project/controller/PhabricatorProjectController.php
@@ -99,7 +99,6 @@
         $nav->addFilter("board/{$id}/", pht('Workboard'));
         $nav->addFilter("members/{$id}/", pht('Members'));
         $nav->addFilter("feed/{$id}/", pht('Feed'));
-        $nav->addFilter("details/{$id}/", pht('Edit Details'));
       }
       $nav->addFilter('create', pht('Create Project'));
     }
@@ -149,11 +148,29 @@
 
     $nav->addIcon("feed/{$id}/", pht('Feed'), 'fa-newspaper-o');
     $nav->addIcon("members/{$id}/", pht('Members'), 'fa-group');
-    $nav->addIcon("details/{$id}/", pht('Edit Details'), 'fa-pencil');
 
     if (PhabricatorEnv::getEnvConfig('phabricator.show-prototypes')) {
-      $nav->addIcon("subprojects/{$id}/", pht('Subprojects'), 'fa-sitemap');
-      $nav->addIcon("milestones/{$id}/", pht('Milestones'), 'fa-map-marker');
+      if ($project->supportsSubprojects()) {
+        $subprojects_icon = 'fa-sitemap';
+      } else {
+        $subprojects_icon = 'fa-sitemap grey';
+      }
+
+      if ($project->supportsMilestones()) {
+        $milestones_icon = 'fa-map-marker';
+      } else {
+        $milestones_icon = 'fa-map-marker grey';
+      }
+
+      $nav->addIcon(
+        "subprojects/{$id}/",
+        pht('Subprojects'),
+        $subprojects_icon);
+
+      $nav->addIcon(
+        "milestones/{$id}/",
+        pht('Milestones'),
+        $milestones_icon);
     }
 
 
@@ -170,8 +187,8 @@
       $ancestors[] = $project;
       foreach ($ancestors as $ancestor) {
         $crumbs->addTextCrumb(
-          $project->getName(),
-          $project->getURI());
+          $ancestor->getName(),
+          $ancestor->getURI());
       }
     }
 
diff --git a/src/applications/project/controller/PhabricatorProjectEditController.php b/src/applications/project/controller/PhabricatorProjectEditController.php
--- a/src/applications/project/controller/PhabricatorProjectEditController.php
+++ b/src/applications/project/controller/PhabricatorProjectEditController.php
@@ -3,10 +3,111 @@
 final class PhabricatorProjectEditController
   extends PhabricatorProjectController {
 
+  private $engine;
+
+  public function setEngine(PhabricatorProjectEditEngine $engine) {
+    $this->engine = $engine;
+    return $this;
+  }
+
+  public function getEngine() {
+    return $this->engine;
+  }
+
   public function handleRequest(AphrontRequest $request) {
-    return id(new PhabricatorProjectEditEngine())
-      ->setController($this)
-      ->buildResponse();
+    $viewer = $this->getViewer();
+
+    $engine = id(new PhabricatorProjectEditEngine())
+      ->setController($this);
+
+    $this->setEngine($engine);
+
+    $id = $request->getURIData('id');
+    if (!$id) {
+      $parent_id = head($request->getArr('parent'));
+      if (!$parent_id) {
+        $parent_id = $request->getStr('parent');
+      }
+
+      if ($parent_id) {
+        $is_milestone = false;
+      } else {
+        $parent_id = head($request->getArr('milestone'));
+        if (!$parent_id) {
+          $parent_id = $request->getStr('milestone');
+        }
+        $is_milestone = true;
+      }
+
+      if ($parent_id) {
+        $query = id(new PhabricatorProjectQuery())
+          ->setViewer($viewer)
+          ->requireCapabilities(
+            array(
+              PhabricatorPolicyCapability::CAN_VIEW,
+              PhabricatorPolicyCapability::CAN_EDIT,
+            ));
+
+        if (ctype_digit($parent_id)) {
+          $query->withIDs(array($parent_id));
+        } else {
+          $query->withPHIDs(array($parent_id));
+        }
+
+        $parent = $query->executeOne();
+
+        if ($is_milestone) {
+          if (!$parent->supportsMilestones()) {
+            $cancel_uri = "/project/milestones/{$parent_id}/";
+            return $this->newDialog()
+              ->setTitle(pht('No Milestones'))
+              ->appendParagraph(
+                pht('You can not add milestones to this project.'))
+              ->addCancelButton($cancel_uri);
+          }
+          $engine->setMilestoneProject($parent);
+        } else {
+          if (!$parent->supportsSubprojects()) {
+            $cancel_uri = "/project/subprojects/{$parent_id}/";
+            return $this->newDialog()
+              ->setTitle(pht('No Subprojects'))
+              ->appendParagraph(
+                pht('You can not add subprojects to this project.'))
+              ->addCancelButton($cancel_uri);
+          }
+          $engine->setParentProject($parent);
+        }
+
+        $this->setProject($parent);
+      }
+    }
+
+    return $engine->buildResponse();
+  }
+
+  protected function buildApplicationCrumbs() {
+    $crumbs = parent::buildApplicationCrumbs();
+
+    $engine = $this->getEngine();
+    if ($engine) {
+      $parent = $engine->getParentProject();
+      if ($parent) {
+        $id = $parent->getID();
+        $crumbs->addTextCrumb(
+          pht('Subprojects'),
+          $this->getApplicationURI("subprojects/{$id}/"));
+      }
+
+      $milestone = $engine->getMilestoneProject();
+      if ($milestone) {
+        $id = $milestone->getID();
+        $crumbs->addTextCrumb(
+          pht('Milestones'),
+          $this->getApplicationURI("milestones/{$id}/"));
+      }
+    }
+
+    return $crumbs;
   }
 
 }
diff --git a/src/applications/project/controller/PhabricatorProjectMembersEditController.php b/src/applications/project/controller/PhabricatorProjectMembersEditController.php
--- a/src/applications/project/controller/PhabricatorProjectMembersEditController.php
+++ b/src/applications/project/controller/PhabricatorProjectMembersEditController.php
@@ -68,9 +68,11 @@
       $project,
       PhabricatorPolicyCapability::CAN_EDIT);
 
+    $supports_edit = $project->supportsEditMembers();
+
     $form_box = null;
     $title = pht('Add Members');
-    if ($can_edit) {
+    if ($can_edit && $supports_edit) {
       $header_name = pht('Edit Members');
       $view_uri = $this->getApplicationURI('profile/'.$project->getID().'/');
 
diff --git a/src/applications/project/controller/PhabricatorProjectMilestonesController.php b/src/applications/project/controller/PhabricatorProjectMilestonesController.php
--- a/src/applications/project/controller/PhabricatorProjectMilestonesController.php
+++ b/src/applications/project/controller/PhabricatorProjectMilestonesController.php
@@ -18,6 +18,64 @@
     $project = $this->getProject();
     $id = $project->getID();
 
+    $can_edit = PhabricatorPolicyFilter::hasCapability(
+      $viewer,
+      $project,
+      PhabricatorPolicyCapability::CAN_EDIT);
+
+    $has_support = $project->supportsMilestones();
+    if ($has_support) {
+      $milestones = id(new PhabricatorProjectQuery())
+        ->setViewer($viewer)
+        ->withParentProjectPHIDs(array($project->getPHID()))
+        ->needImages(true)
+        ->withIsMilestone(true)
+        ->setOrder('newest')
+        ->execute();
+    } else {
+      $milestones = array();
+    }
+
+    $can_create = $can_edit && $has_support;
+
+    if ($project->getHasMilestones()) {
+      $button_text = pht('Create Next Milestone');
+    } else {
+      $button_text = pht('Add Milestones');
+    }
+
+    $header = id(new PHUIHeaderView())
+      ->setHeader(pht('Milestones'))
+      ->addActionLink(
+        id(new PHUIButtonView())
+          ->setTag('a')
+          ->setHref("/project/edit/?milestone={$id}")
+          ->setIconFont('fa-plus')
+          ->setDisabled(!$can_create)
+          ->setWorkflow(!$can_create)
+          ->setText($button_text));
+
+    $box = id(new PHUIObjectBoxView())
+      ->setHeader($header);
+
+    if (!$has_support) {
+      $no_support = pht(
+        'This project is a milestone. Milestones can not have their own '.
+        'milestones.');
+
+      $info_view = id(new PHUIInfoView())
+        ->setErrors(array($no_support))
+        ->setSeverity(PHUIInfoView::SEVERITY_WARNING);
+
+      $box->setInfoView($info_view);
+    }
+
+    $box->setObjectList(
+      id(new PhabricatorProjectListView())
+        ->setUser($viewer)
+        ->setProjects($milestones)
+        ->renderList());
+
     $nav = $this->buildIconNavView($project);
     $nav->selectFilter("milestones/{$id}/");
 
@@ -27,7 +85,8 @@
     return $this->newPage()
       ->setNavigation($nav)
       ->setCrumbs($crumbs)
-      ->setTitle(array($project->getName(), pht('Milestones')));
+      ->setTitle(array($project->getName(), pht('Milestones')))
+      ->appendChild($box);
   }
 
 }
diff --git a/src/applications/project/controller/PhabricatorProjectSubprojectsController.php b/src/applications/project/controller/PhabricatorProjectSubprojectsController.php
--- a/src/applications/project/controller/PhabricatorProjectSubprojectsController.php
+++ b/src/applications/project/controller/PhabricatorProjectSubprojectsController.php
@@ -18,6 +18,63 @@
     $project = $this->getProject();
     $id = $project->getID();
 
+    $can_edit = PhabricatorPolicyFilter::hasCapability(
+      $viewer,
+      $project,
+      PhabricatorPolicyCapability::CAN_EDIT);
+
+    $has_support = $project->supportsSubprojects();
+
+    if ($has_support) {
+      $subprojects = id(new PhabricatorProjectQuery())
+        ->setViewer($viewer)
+        ->withParentProjectPHIDs(array($project->getPHID()))
+        ->needImages(true)
+        ->withIsMilestone(false)
+        ->execute();
+    } else {
+      $subprojects = array();
+    }
+
+    $can_create = $can_edit && $has_support;
+
+    if ($project->getHasSubprojects()) {
+      $button_text = pht('Create Subproject');
+    } else {
+      $button_text = pht('Add Subprojects');
+    }
+
+    $header = id(new PHUIHeaderView())
+      ->setHeader(pht('Subprojects'))
+      ->addActionLink(
+        id(new PHUIButtonView())
+          ->setTag('a')
+          ->setHref("/project/edit/?parent={$id}")
+          ->setIconFont('fa-plus')
+          ->setDisabled(!$can_create)
+          ->setWorkflow(!$can_create)
+          ->setText($button_text));
+
+    $box = id(new PHUIObjectBoxView())
+      ->setHeader($header);
+
+    if (!$has_support) {
+      $no_support = pht(
+        'This project is a milestone. Milestones can not have subprojects.');
+
+      $info_view = id(new PHUIInfoView())
+        ->setErrors(array($no_support))
+        ->setSeverity(PHUIInfoView::SEVERITY_WARNING);
+
+      $box->setInfoView($info_view);
+    }
+
+    $box->setObjectList(
+      id(new PhabricatorProjectListView())
+        ->setUser($viewer)
+        ->setProjects($subprojects)
+        ->renderList());
+
     $nav = $this->buildIconNavView($project);
     $nav->selectFilter("subprojects/{$id}/");
 
@@ -27,7 +84,8 @@
     return $this->newPage()
       ->setNavigation($nav)
       ->setCrumbs($crumbs)
-      ->setTitle(array($project->getName(), pht('Subprojects')));
+      ->setTitle(array($project->getName(), pht('Subprojects')))
+      ->appendChild($box);
   }
 
 }
diff --git a/src/applications/project/editor/PhabricatorProjectTransactionEditor.php b/src/applications/project/editor/PhabricatorProjectTransactionEditor.php
--- a/src/applications/project/editor/PhabricatorProjectTransactionEditor.php
+++ b/src/applications/project/editor/PhabricatorProjectTransactionEditor.php
@@ -74,23 +74,10 @@
       case PhabricatorProjectTransaction::TYPE_COLOR:
       case PhabricatorProjectTransaction::TYPE_LOCKED:
       case PhabricatorProjectTransaction::TYPE_PARENT:
+      case PhabricatorProjectTransaction::TYPE_MILESTONE:
         return $xaction->getNewValue();
       case PhabricatorProjectTransaction::TYPE_SLUGS:
         return $this->normalizeSlugs($xaction->getNewValue());
-      case PhabricatorProjectTransaction::TYPE_MILESTONE:
-        $current = queryfx_one(
-          $object->establishConnection('w'),
-          'SELECT MAX(milestoneNumber) n
-            FROM %T
-            WHERE parentProjectPHID = %s',
-          $object->getTableName(),
-          $object->getParentProject()->getPHID());
-        if (!$current) {
-          $number = 1;
-        } else {
-          $number = (int)$current['n'] + 1;
-        }
-        return $number;
     }
 
     return parent::getCustomTransactionNewValue($object, $xaction);
@@ -127,7 +114,21 @@
         $object->setParentProjectPHID($xaction->getNewValue());
         return;
       case PhabricatorProjectTransaction::TYPE_MILESTONE:
-        $object->setMilestoneNumber($xaction->getNewValue());
+        $current = queryfx_one(
+          $object->establishConnection('w'),
+          'SELECT MAX(milestoneNumber) n
+            FROM %T
+            WHERE parentProjectPHID = %s',
+          $object->getTableName(),
+          $object->getParentProject()->getPHID());
+        if (!$current) {
+          $number = 1;
+        } else {
+          $number = (int)$current['n'] + 1;
+        }
+
+        $object->setMilestoneNumber($number);
+        $object->setParentProjectPHID($xaction->getNewValue());
         return;
     }
 
@@ -239,6 +240,84 @@
     return parent::applyBuiltinExternalTransaction($object, $xaction);
   }
 
+  protected function validateAllTransactions(
+    PhabricatorLiskDAO $object,
+    array $xactions) {
+
+    $errors = array();
+
+    // Prevent creating projects which are both subprojects and milestones,
+    // since this does not make sense, won't work, and will break everything.
+    $parent_xaction = null;
+    foreach ($xactions as $xaction) {
+      switch ($xaction->getTransactionType()) {
+        case PhabricatorProjectTransaction::TYPE_PARENT:
+        case PhabricatorProjectTransaction::TYPE_MILESTONE:
+          if ($xaction->getNewValue() === null) {
+            continue;
+          }
+
+          if (!$parent_xaction) {
+            $parent_xaction = $xaction;
+            continue;
+          }
+
+          $errors[] = new PhabricatorApplicationTransactionValidationError(
+            $xaction->getTransactionType(),
+            pht('Invalid'),
+            pht(
+              'When creating a project, specify a maximum of one parent '.
+              'project or milestone project. A project can not be both a '.
+              'subproject and a milestone.'),
+            $xaction);
+          break;
+          break;
+      }
+    }
+
+    $is_milestone = $object->isMilestone();
+    foreach ($xactions as $xaction) {
+      switch ($xaction->getTransactionType()) {
+        case PhabricatorProjectTransaction::TYPE_MILESTONE:
+          if ($xaction->getNewValue() !== null) {
+            $is_milestone = true;
+          }
+          break;
+      }
+    }
+
+    $is_parent = $object->getHasSubprojects();
+
+    foreach ($xactions as $xaction) {
+      switch ($xaction->getTransactionType()) {
+        case PhabricatorProjectTransaction::TYPE_MEMBERS:
+          if ($is_parent) {
+            $errors[] = new PhabricatorApplicationTransactionValidationError(
+              $xaction->getTransactionType(),
+              pht('Invalid'),
+              pht(
+                'You can not change members of a project with subprojects '.
+                'directly. Members of any subproject are automatically '.
+                'members of the parent project.'),
+              $xaction);
+          }
+
+          if ($is_milestone) {
+            $errors[] = new PhabricatorApplicationTransactionValidationError(
+              $xaction->getTransactionType(),
+              pht('Invalid'),
+              pht(
+                'You can not change members of a milestone. Members of the '.
+                'parent project are automatically members of the milestone.'),
+              $xaction);
+          }
+          break;
+      }
+    }
+
+    return $errors;
+  }
+
   protected function validateTransaction(
     PhabricatorLiskDAO $object,
     $type,
@@ -367,25 +446,29 @@
 
         break;
       case PhabricatorProjectTransaction::TYPE_PARENT:
+      case PhabricatorProjectTransaction::TYPE_MILESTONE:
         if (!$xactions) {
           break;
         }
 
         $xaction = last($xactions);
 
+        $parent_phid = $xaction->getNewValue();
+        if (!$parent_phid) {
+          continue;
+        }
+
         if (!$this->getIsNewObject()) {
           $errors[] = new PhabricatorApplicationTransactionValidationError(
             $type,
             pht('Invalid'),
             pht(
-              'You can only set a parent project when creating a project '.
-              'for the first time.'),
+              'You can only set a parent or milestone project when creating a '.
+              'project for the first time.'),
             $xaction);
           break;
         }
 
-        $parent_phid = $xaction->getNewValue();
-
         $projects = id(new PhabricatorProjectQuery())
           ->setViewer($this->requireActor())
           ->withPHIDs(array($parent_phid))
@@ -400,8 +483,8 @@
             $type,
             pht('Invalid'),
             pht(
-              'Parent project PHID ("%s") must be the PHID of a valid, '.
-              'visible project which you have permission to edit.',
+              'Parent or milestone project PHID ("%s") must be the PHID of a '.
+              'valid, visible project which you have permission to edit.',
               $parent_phid),
             $xaction);
           break;
@@ -414,8 +497,8 @@
             $type,
             pht('Invalid'),
             pht(
-              'Parent project PHID ("%s") must not be a milestone. '.
-              'Milestones may not have subprojects.',
+              'Parent or milestone project PHID ("%s") must not be a '.
+              'milestone. Milestones may not have subprojects or milestones.',
               $parent_phid),
             $xaction);
           break;
@@ -427,9 +510,9 @@
             $type,
             pht('Invalid'),
             pht(
-              'You can not create a subproject under this parent because '.
-              'it would nest projects too deeply. The maximum nesting '.
-              'depth of projects is %s.',
+              'You can not create a subproject or mielstone under this parent '.
+              'because it would nest projects too deeply. The maximum '.
+              'nesting depth of projects is %s.',
               new PhutilNumber($limit)),
             $xaction);
           break;
@@ -611,6 +694,7 @@
     array $xactions) {
 
     $materialize = false;
+    $new_parent = null;
     foreach ($xactions as $xaction) {
       switch ($xaction->getTransactionType()) {
         case PhabricatorTransactions::TYPE_EDGE:
@@ -622,10 +706,34 @@
           break;
         case PhabricatorProjectTransaction::TYPE_PARENT:
           $materialize = true;
+          $new_parent = $object->getParentProject();
           break;
       }
     }
 
+    if ($new_parent) {
+      // If we just created the first subproject of this parent, we want to
+      // copy all of the real members to the subproject.
+      if (!$new_parent->getHasSubprojects()) {
+        $member_type = PhabricatorProjectProjectHasMemberEdgeType::EDGECONST;
+
+        $project_members = PhabricatorEdgeQuery::loadDestinationPHIDs(
+          $new_parent->getPHID(),
+          $member_type);
+
+        if ($project_members) {
+          $editor = id(new PhabricatorEdgeEditor());
+          foreach ($project_members as $phid) {
+            $editor->addEdge($object->getPHID(), $member_type, $phid);
+          }
+          $editor->save();
+        }
+      }
+    }
+
+    // TODO: We should dump an informational transaction onto the parent
+    // project to show that we created the sub-thing.
+
     if ($materialize) {
       id(new PhabricatorProjectsMembershipIndexEngineExtension())
         ->rematerialize($object);
diff --git a/src/applications/project/engine/PhabricatorProjectEditEngine.php b/src/applications/project/engine/PhabricatorProjectEditEngine.php
--- a/src/applications/project/engine/PhabricatorProjectEditEngine.php
+++ b/src/applications/project/engine/PhabricatorProjectEditEngine.php
@@ -5,6 +5,27 @@
 
   const ENGINECONST = 'projects.project';
 
+  private $parentProject;
+  private $milestoneProject;
+
+  public function setParentProject(PhabricatorProject $parent_project) {
+    $this->parentProject = $parent_project;
+    return $this;
+  }
+
+  public function getParentProject() {
+    return $this->parentProject;
+  }
+
+  public function setMilestoneProject(PhabricatorProject $milestone_project) {
+    $this->milestoneProject = $milestone_project;
+    return $this;
+  }
+
+  public function getMilestoneProject() {
+    return $this->milestoneProject;
+  }
+
   public function getEngineName() {
     return pht('Projects');
   }
@@ -50,6 +71,22 @@
     return $object->getURI();
   }
 
+  protected function getObjectCreateCancelURI($object) {
+    $parent = $this->getParentProject();
+    if ($parent) {
+      $id = $parent->getID();
+      return "/project/subprojects/{$id}/";
+    }
+
+    $milestone = $this->getMilestoneProject();
+    if ($milestone) {
+      $id = $milestone->getID();
+      return "/project/milestones/{$id}/";
+    }
+
+    return parent::getObjectCreateCancelURI($object);
+  }
+
   protected function getCreateNewObjectPolicy() {
     return $this->getApplication()->getPolicy(
       ProjectCreateProjectsCapability::CAPABILITY);
@@ -65,6 +102,8 @@
     $configuration
       ->setFieldOrder(
         array(
+          'parent',
+          'milestone',
           'name',
           'std:project:internal:description',
           'icon',
@@ -84,7 +123,52 @@
     unset($slugs[$object->getPrimarySlug()]);
     $slugs = array_values($slugs);
 
+    $milestone = $this->getMilestoneProject();
+    $parent = $this->getParentProject();
+
+    if ($parent) {
+      $parent_phid = $parent->getPHID();
+    } else {
+      $parent_phid = null;
+    }
+
+    if ($milestone) {
+      $milestone_phid = $milestone->getPHID();
+    } else {
+      $milestone_phid = null;
+    }
+
     return array(
+      id(new PhabricatorHandlesEditField())
+        ->setKey('parent')
+        ->setLabel(pht('Parent'))
+        ->setDescription(pht('Create a subproject of an existing project.'))
+        ->setConduitDescription(
+          pht('Choose a parent project to create a subproject beneath.'))
+        ->setConduitTypeDescription(pht('PHID of the parent project.'))
+        ->setAliases(array('parentPHID'))
+        ->setTransactionType(PhabricatorProjectTransaction::TYPE_PARENT)
+        ->setHandleParameterType(new AphrontPHIDHTTPParameterType())
+        ->setSingleValue($parent_phid)
+        ->setIsReorderable(false)
+        ->setIsDefaultable(false)
+        ->setIsLockable(false)
+        ->setIsLocked(true),
+      id(new PhabricatorHandlesEditField())
+        ->setKey('milestone')
+        ->setLabel(pht('Milestone Of'))
+        ->setDescription(pht('Parent project to create a milestone for.'))
+        ->setConduitDescription(
+          pht('Choose a parent project to create a new milestone for.'))
+        ->setConduitTypeDescription(pht('PHID of the parent project.'))
+        ->setAliases(array('milestonePHID'))
+        ->setTransactionType(PhabricatorProjectTransaction::TYPE_MILESTONE)
+        ->setHandleParameterType(new AphrontPHIDHTTPParameterType())
+        ->setSingleValue($milestone_phid)
+        ->setIsReorderable(false)
+        ->setIsDefaultable(false)
+        ->setIsLockable(false)
+        ->setIsLocked(true),
       id(new PhabricatorTextEditField())
         ->setKey('name')
         ->setLabel(pht('Name'))
diff --git a/src/applications/project/query/PhabricatorProjectSearchEngine.php b/src/applications/project/query/PhabricatorProjectSearchEngine.php
--- a/src/applications/project/query/PhabricatorProjectSearchEngine.php
+++ b/src/applications/project/query/PhabricatorProjectSearchEngine.php
@@ -164,42 +164,15 @@
     array $handles) {
     assert_instances_of($projects, 'PhabricatorProject');
     $viewer = $this->requireViewer();
-    $handles = $viewer->loadHandles(mpull($projects, 'getPHID'));
-
-    $list = new PHUIObjectItemListView();
-    $list->setUser($viewer);
-    $can_edit_projects = id(new PhabricatorPolicyFilter())
-      ->setViewer($viewer)
-      ->requireCapabilities(array(PhabricatorPolicyCapability::CAN_EDIT))
-      ->apply($projects);
-
-    foreach ($projects as $key => $project) {
-      $id = $project->getID();
-
-      $tag_list = id(new PHUIHandleTagListView())
-        ->setSlim(true)
-        ->setHandles(array($handles[$project->getPHID()]));
-
-      $item = id(new PHUIObjectItemView())
-        ->setHeader($project->getName())
-        ->setHref($this->getApplicationURI("view/{$id}/"))
-        ->setImageURI($project->getProfileImageURI())
-        ->addAttribute($tag_list);
-
-      if ($project->getStatus() == PhabricatorProjectStatus::STATUS_ARCHIVED) {
-        $item->addIcon('delete-grey', pht('Archived'));
-        $item->setDisabled(true);
-      }
-
-      $list->addItem($item);
-    }
-
-    $result = new PhabricatorApplicationSearchResultView();
-    $result->setObjectList($list);
-    $result->setNoDataString(pht('No projects found.'));
 
-    return $result;
+    $list = id(new PhabricatorProjectListView())
+      ->setUser($viewer)
+      ->setProjects($projects)
+      ->renderList();
 
+    return id(new PhabricatorApplicationSearchResultView())
+      ->setObjectList($list)
+      ->setNoDataString(pht('No projects found.'));
   }
 
   protected function getNewUserBody() {
diff --git a/src/applications/project/storage/PhabricatorProject.php b/src/applications/project/storage/PhabricatorProject.php
--- a/src/applications/project/storage/PhabricatorProject.php
+++ b/src/applications/project/storage/PhabricatorProject.php
@@ -88,6 +88,10 @@
   }
 
   public function getPolicy($capability) {
+    if ($this->isMilestone()) {
+      return $this->getParentProject()->getPolicy($capability);
+    }
+
     switch ($capability) {
       case PhabricatorPolicyCapability::CAN_VIEW:
         return $this->getViewPolicy();
@@ -99,6 +103,12 @@
   }
 
   public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
+    if ($this->isMilestone()) {
+      return $this->getParentProject()->hasAutomaticCapability(
+        $capability,
+        $viewer);
+    }
+
     $can_edit = PhabricatorPolicyCapability::CAN_EDIT;
 
     switch ($capability) {
@@ -437,6 +447,34 @@
     return $ancestors;
   }
 
+  public function supportsEditMembers() {
+    if ($this->isMilestone()) {
+      return false;
+    }
+
+    if ($this->getHasSubprojects()) {
+      return false;
+    }
+
+    return true;
+  }
+
+  public function supportsMilestones() {
+    if ($this->isMilestone()) {
+      return false;
+    }
+
+    return true;
+  }
+
+  public function supportsSubprojects() {
+    if ($this->isMilestone()) {
+      return false;
+    }
+
+    return true;
+  }
+
 
 /* -(  PhabricatorSubscribableInterface  )----------------------------------- */
 
diff --git a/src/applications/project/view/PhabricatorProjectListView.php b/src/applications/project/view/PhabricatorProjectListView.php
new file mode 100644
--- /dev/null
+++ b/src/applications/project/view/PhabricatorProjectListView.php
@@ -0,0 +1,53 @@
+<?php
+
+final class PhabricatorProjectListView extends AphrontView {
+
+  private $projects;
+
+  public function setProjects(array $projects) {
+    $this->projects = $projects;
+    return $this;
+  }
+
+  public function getProjects() {
+    return $this->projects;
+  }
+
+  public function renderList() {
+    $viewer = $this->getUser();
+    $projects = $this->getProjects();
+
+    $handles = $viewer->loadHandles(mpull($projects, 'getPHID'));
+
+    $list = id(new PHUIObjectItemListView())
+      ->setUser($viewer);
+
+    foreach ($projects as $key => $project) {
+      $id = $project->getID();
+
+      $tag_list = id(new PHUIHandleTagListView())
+        ->setSlim(true)
+        ->setHandles(array($handles[$project->getPHID()]));
+
+      $item = id(new PHUIObjectItemView())
+        ->setHeader($project->getName())
+        ->setHref("/project/view/{$id}/")
+        ->setImageURI($project->getProfileImageURI())
+        ->addAttribute($tag_list);
+
+      if ($project->getStatus() == PhabricatorProjectStatus::STATUS_ARCHIVED) {
+        $item->addIcon('delete-grey', pht('Archived'));
+        $item->setDisabled(true);
+      }
+
+      $list->addItem($item);
+    }
+
+    return $list;
+  }
+
+  public function render() {
+    return $this->renderList();
+  }
+
+}
diff --git a/webroot/rsrc/css/layout/phabricator-side-menu-view.css b/webroot/rsrc/css/layout/phabricator-side-menu-view.css
--- a/webroot/rsrc/css/layout/phabricator-side-menu-view.css
+++ b/webroot/rsrc/css/layout/phabricator-side-menu-view.css
@@ -89,6 +89,10 @@
   color: {$blue};
 }
 
+.phabricator-icon-nav .phabricator-side-menu .phui-list-item-icon.grey {
+  color: {$lightgreyborder};
+}
+
 .phabricator-icon-nav .phabricator-side-menu .phui-list-item-selected {
   border: none;
 }