diff -r ab6209ce77b6 Lib/idlelib/AutoComplete.py
--- a/Lib/idlelib/AutoComplete.py	Fri Jun 20 17:34:44 2014 +0200
+++ b/Lib/idlelib/AutoComplete.py	Fri Jun 20 14:07:56 2014 -0300
@@ -13,7 +13,7 @@
 ID_CHARS = string.ascii_letters + string.digits + "_"
 
 # These constants represent the two different types of completions
-COMPLETE_ATTRIBUTES, COMPLETE_FILES = range(1, 2+1)
+COMPLETE_ATTRIBUTES, COMPLETE_FILES, COMPLETE_DICTIONARY = range(1, 3+1)
 
 from idlelib import AutoCompleteWindow
 from idlelib.HyperParser import HyperParser
@@ -120,7 +120,18 @@
         hp = HyperParser(self.editwin, "insert")
         curline = self.text.get("insert linestart", "insert")
         i = j = len(curline)
-        if hp.is_in_string() and (not mode or mode==COMPLETE_FILES):
+        if hp.is_in_subscript_string() and (not mode or mode==COMPLETE_DICTIONARY):
+            self._remove_autocomplete_window()
+            mode = COMPLETE_DICTIONARY
+            while i and (curline[i-1] not in "'"):
+                i -= 1
+            comp_start = curline[i:j]
+            if i > 1 and curline[i-2] == '[':
+                hp.set_index("insert-%dc" % (len(curline)-(i-2)))
+                comp_what = hp.get_expression()
+            else:
+                comp_what = ""
+        elif hp.is_in_string() and (not mode or mode==COMPLETE_FILES):
             # Find the beginning of the string
             # fetch_completions will look at the file system to determine whether the
             # string value constitutes an actual file name
@@ -184,6 +195,7 @@
             return rpcclt.remotecall("exec", "get_the_completion_list",
                                      (what, mode), {})
         else:
+            smalll = bigl = None
             if mode == COMPLETE_ATTRIBUTES:
                 if what == "":
                     namespace = __main__.__dict__.copy()
@@ -217,6 +229,14 @@
                 except OSError:
                     return [], []
 
+            elif mode == COMPLETE_DICTIONARY:
+                try:
+                    entity = self.get_entity(what)
+                    bigl = [s for s in entity.keys() if isinstance(s,str)]
+                    bigl.sort()
+                except:
+                    return [], []
+
             if not smalll:
                 smalll = bigl
             return smalll, bigl
diff -r ab6209ce77b6 Lib/idlelib/HyperParser.py
--- a/Lib/idlelib/HyperParser.py	Fri Jun 20 17:34:44 2014 +0200
+++ b/Lib/idlelib/HyperParser.py	Fri Jun 20 14:07:56 2014 -0300
@@ -87,6 +87,15 @@
            not self.isopener[self.indexbracket+1]):
             self.indexbracket += 1
 
+    def is_in_subscript_string(self):
+        """Is the index given to the HyperParser in a string inside
+        a subscript?
+        """
+        return (self.indexbracket and
+                self.is_in_string() and
+                self.isopener[self.indexbracket-1] and
+                self.rawtext[self.bracketing[self.indexbracket-1][0]] == '[')
+
     def is_in_string(self):
         """Is the index given to the HyperParser in a string?"""
         # The bracket to which we belong should be an opener.
diff -r ab6209ce77b6 Lib/idlelib/idle_test/test_hyperparser.py
--- a/Lib/idlelib/idle_test/test_hyperparser.py	Fri Jun 20 17:34:44 2014 +0200
+++ b/Lib/idlelib/idle_test/test_hyperparser.py	Fri Jun 20 14:07:56 2014 -0300
@@ -30,6 +30,9 @@
             "z = ((r'asdf')+('a')))\n"
             '[x for x in\n'
             'for = False\n'
+            "d['a']\n"
+            'd["a"]\n'
+            "d[1]\n"
             )
 
     @classmethod
@@ -78,6 +81,24 @@
         self.text.insert('end', self.text.get('1.0', 'end')*4)
         p = self.get_parser('54.5')
 
+    def test_is_in_subscript_string(self):
+        get = self.get_parser
+
+        p = get('12.0')
+        self.assertFalse(p.is_in_subscript_string())
+        p = get('12.2')
+        self.assertFalse(p.is_in_subscript_string())
+        p = get('12.3')
+        self.assertTrue(p.is_in_subscript_string())
+        p = get('12.5')
+        self.assertFalse(p.is_in_subscript_string())
+        p = get('13.2')
+        self.assertFalse(p.is_in_subscript_string())
+        p = get('13.3')
+        self.assertTrue(p.is_in_subscript_string())
+        p = get('14.2')
+        self.assertFalse(p.is_in_subscript_string())
+
     def test_is_in_string(self):
         get = self.get_parser