diff --git a/fluents/fluents.py b/fluents/fluents.py
index cf1b859..64fe361 100644
--- a/fluents/fluents.py
+++ b/fluents/fluents.py
@@ -197,12 +197,13 @@ class FluentApp:
         tb = ViewFrameToolButton()
         self['toolbar'].add(tb)
 
-    def set_project(self, project):
+    def set_project(self, proj):
         logger.log('notice', 'Creating a new project')
-        self.project = project
-        self.workflow.add_project(self.project)
-        self.navigator_view.add_project(self.project)
-        self.dimlistcontroller.set_project(project)
+        self.project = proj
+        project.project = proj
+        self.workflow.add_project(proj)
+        self.navigator_view.add_project(proj)
+        self.dimlistcontroller.set_project(proj)
 
     def set_workflow(self, workflow):
         self.workflow = workflow
diff --git a/fluents/project.py b/fluents/project.py
index 555393b..ab75992 100644
--- a/fluents/project.py
+++ b/fluents/project.py
@@ -135,3 +135,8 @@ class Project:
     def set_current_data(self, obj):
         self.current_data = obj
 
+
+## Singleton project.
+## This is the current and only project in the application.
+project = None
+
diff --git a/workflows/go_workflow.py b/workflows/go_workflow.py
index 00615ea..d5a8b99 100644
--- a/workflows/go_workflow.py
+++ b/workflows/go_workflow.py
@@ -1,5 +1,5 @@
 import gtk
-from fluents import dataset, logger, plots, workflow, fluents
+from fluents import dataset, logger, plots, workflow, fluents, project
 from fluents.lib import blmfuncs
 import geneontology
 #import gostat
@@ -77,6 +77,11 @@ class GeneOntologyTree (gtk.HPaned):
         self._treemodel = treemodel
         self._tree_view = gtk.TreeView(treemodel)
 
+        # Set up context menu
+        self._context_menu = GoTermContextMenu(treemodel, self._tree_view)
+        self._tree_view.connect('popup_menu', self._popup_menu)
+        self._tree_view.connect('button_press_event', self._on_button_press)
+
         renderer = gtk.CellRendererText()
         go_column = gtk.TreeViewColumn('GO ID', renderer, text=0)
         self._tree_view.insert_column(go_column, 0)
@@ -102,6 +107,54 @@ class GeneOntologyTree (gtk.HPaned):
         self._desc_view.set_go_term(term)        
         
 
+    ##
+    ## GTK Callback functions
+    ##
+    def _popup_menu(self, *rest):
+        self.menu.popup(None, None, None, 0, 0)
+
+    def _on_button_press(self, widget, event):
+        path = widget.get_path_at_pos(int(event.x), int(event.y))
+        iter = None
+
+        if path:
+            iter = self._treemodel.get_iter(path[0])
+            obj = self._treemodel.get_value(iter, 2)
+        else:
+            obj = None
+
+        self._context_menu.set_current_term(obj)
+
+        if event.button == 3:
+            self._context_menu.popup(None, None, None, event.button, event.time)
+
+
+class GoTermContextMenu (gtk.Menu):
+    """Context menu for GO terms in the gene ontology browser"""
+
+    def __init__(self, treemodel, treeview):
+        self._treemodel = treemodel
+        self._treeview = treeview
+        self._current_term = None
+
+        gtk.Menu.__init__(self)
+
+        # Popuplate tree
+        self._select_subtree_item = i = gtk.MenuItem('Select subtree')
+        i.connect('activate', self._on_select_subtree, treemodel, treeview)
+        self.append(i)
+        i.show()
+
+    def set_current_term(self, term):
+        self._current_term = term
+
+    def _on_select_subtree(self, item, treemodel, treeview):
+        logger.log('notice', 'Selecting subtree from GO id: %s (%s)' %
+                   (self._current_term['id'], self._current_term['name']))
+        ids = [x['id'] for x in networkx.bfs(go, self._current_term)]
+        project.project.set_selection('go-terms', set(ids))
+
+
 class GoWorkflow (workflow.Workflow):
 
     name = 'Gene Ontology'