diff --git a/system/selections.py b/system/selections.py
index cb51fdd..90d4ead 100644
--- a/system/selections.py
+++ b/system/selections.py
@@ -30,6 +30,7 @@ class SelectionTree(gtk.TreeView):
         self.insert_column(sel_column, 0)
 
         self.connect('row-activated', self._on_row_activated)
+        self.connect('cursor-changed', self._on_cursor_changed)
 
         self._identifier_list = None
         self._dim_list = {}
@@ -111,15 +112,20 @@ class SelectionTree(gtk.TreeView):
 
     # Callbacks
     def _on_row_activated(self, treeview, path, column):
-        i = self.store.get_iter(path)
+        self.project.set_selection(self._current_dim, 
+                                   self._current_selection[self._current_dim])
+
+    def _on_cursor_changed(self, treeview):        
+        cursor = self.get_cursor()[0]
+        i = self.store.get_iter(cursor)
         p = self.store.iter_parent(i)
         if p == None:
-            pass         
+            self._current_selection = None
         else:
             self._current_dim = self.store.get_value(p, 0)
             self._current_selection = self.store.get_value(i, 1)
         self._update_current_dim()
-        
+
     def _on_set_selection(self, *rest):
         if not self._current_selection:
             return