diff --git a/django/forms/widgets.py b/django/forms/widgets.py
index cb12586..fc80732 100644
--- a/django/forms/widgets.py
+++ b/django/forms/widgets.py
@@ -495,6 +495,8 @@ class CheckboxInput(Widget):
         return bool(initial) != bool(data)
 
 class Select(Widget):
+    allow_multiple_selected = False
+
     def __init__(self, attrs=None, choices=()):
         super(Select, self).__init__(attrs)
         # choices can be any iterable, but we may need to render this widget
@@ -514,7 +516,13 @@ class Select(Widget):
 
     def render_option(self, selected_choices, option_value, option_label):
         option_value = force_unicode(option_value)
-        selected_html = (option_value in selected_choices) and u' selected="selected"' or ''
+        if option_value in selected_choices:
+            selected_html = u' selected="selected"'
+            if not self.allow_multiple_selected:
+                # Only allow for a single selection.
+                selected_choices.remove(option_value)
+        else:
+            selected_html = ''
         return u'<option value="%s"%s>%s</option>' % (
             escape(option_value), selected_html,
             conditional_escape(force_unicode(option_label)))
@@ -567,6 +575,8 @@ class NullBooleanSelect(Select):
         return initial != data
 
 class SelectMultiple(Select):
+    allow_multiple_selected = True
+
     def render(self, name, value, attrs=None, choices=()):
         if value is None: value = []
         final_attrs = self.build_attrs(attrs, name=name)
diff --git a/tests/regressiontests/forms/widgets.py b/tests/regressiontests/forms/widgets.py
index 10483a7..785b302 100644
--- a/tests/regressiontests/forms/widgets.py
+++ b/tests/regressiontests/forms/widgets.py
@@ -463,6 +463,28 @@ over multiple times without getting consumed:
 <option value="4">4</option>
 </select>
 
+Only one option can be selected:
+>>> print w.render('choices', 0, choices=(('0', 'extra'),))
+<select name="choices">
+<option value="0" selected="selected">0</option>
+<option value="1">1</option>
+<option value="2">2</option>
+<option value="3">3</option>
+<option value="4">4</option>
+<option value="0">extra</option>
+</select>
+
+Ensure that it still selects the first element next time round:
+>>> print w.render('choices', 0, choices=(('0', 'extra'),))
+<select name="choices">
+<option value="0" selected="selected">0</option>
+<option value="1">1</option>
+<option value="2">2</option>
+<option value="3">3</option>
+<option value="4">4</option>
+<option value="0">extra</option>
+</select>
+
 Choices can be nested one level in order to create HTML optgroups:
 >>> w.choices=(('outer1', 'Outer 1'), ('Group "1"', (('inner1', 'Inner 1'), ('inner2', 'Inner 2'))))
 >>> print w.render('nestchoice', None)
@@ -674,6 +696,15 @@ True
 >>> w._has_changed([1, 2], [u'1', u'3'])
 True
 
+Multiple options (with the same value) can be selected:
+>>> print w.render('choices', [1], choices=(('1', 'extra'),))
+<select multiple="multiple" name="choices">
+<option value="1" selected="selected">1</option>
+<option value="2">2</option>
+<option value="3">3</option>
+<option value="1" selected="selected">extra</option>
+</select>
+
 # Choices can be nested one level in order to create HTML optgroups:
 >>> w.choices = (('outer1', 'Outer 1'), ('Group "1"', (('inner1', 'Inner 1'), ('inner2', 'Inner 2'))))
 >>> print w.render('nestchoice', None)