diff --git a/fluents/selections.py b/fluents/selections.py
index f7a0165..7f93d0e 100644
--- a/fluents/selections.py
+++ b/fluents/selections.py
@@ -5,6 +5,7 @@ import gtk.glade
 import gnome
 import gnome.ui
 import gobject
+import scipy
 
 import logger, dataset, main
 import annotations
@@ -38,7 +39,7 @@ class IdListController:
 
         # id, annotation
         self._idstore = gtk.ListStore(gobject.TYPE_STRING,
-                                      gobject.TYPE_STRING,)
+                                      gobject.TYPE_STRING)
         self._idstore.set_sort_func(0, self._numeric_compare)
         
         # Annotation tree column
@@ -55,6 +56,12 @@ class IdListController:
         idlist.insert_column(dim_column, 0)
         idlist.connect('button-press-event', self._button_pressed)
 
+        ## Enable dropping
+        idlist.drag_dest_set(gtk.DEST_DEFAULT_ALL,
+                              [("GTK_TREE_MODEL_ROW", gtk.TARGET_SAME_APP, 7)],
+                              gtk.gdk.ACTION_LINK)
+        idlist.connect('drag-data-received', self._drag_data_received)
+
         ## Set up identifier list context menu
         menu = self._menu = SimpleMenu()
         menu.add_simple_item('Import...', self._on_import_list)
@@ -179,6 +186,22 @@ class IdListController:
             print "unknown; ", retval 
         dialog.destroy()
 
+    def set_rank(self, ds):
+        print "Set rank."
+
+        ra = scipy.sum(ds.asarray(), 1)
+        ranks = {}
+        dim = ds.get_dim_name()[0]
+        for key, value in ds[dim].items():
+            ranks[key] = ra[value]
+
+        ann_h = annotations.get_dim_handler(self._dimension)
+        if ann_h is None:
+            ann_h = annotations.DictAnnotationHandler()
+            annotations.set_dim_handler(self._dimension, ann_h)
+
+        ann_h.add_annotations('Rank', ranks)
+
     ##
     ## GTK Callbacks
     ##
@@ -223,6 +246,20 @@ class IdListController:
         ids = [self._idstore.get_value(i, 0) for i in iters]
         main.project.set_selection(self._dimension, ids)
         
+    def _drag_data_received(self, widget, drag_context, x, y,
+                              selection, info, timestamp):
+        print "drag_data_received"
+
+        treestore, path = selection.tree_get_row_drag_data()
+        i = treestore.get_iter(path)
+        obj = treestore.get_value(i, 2)
+        if isinstance(obj, dataset.Dataset):
+            print "is dataset"
+            if self._dimension in obj.get_dim_name():
+                print "has correct dimensions"
+                self.set_rank(obj)
+        widget.emit_stop_by_name('drag-data-received')
+
 
 class SelectionListController:
     def __init__(self, seltree, idlist_controller):