diff -r da9898e7e90d Lib/test/test_xml_etree.py
--- a/Lib/test/test_xml_etree.py	Wed Jul 27 16:59:22 2016 +0200
+++ b/Lib/test/test_xml_etree.py	Wed Jul 27 19:56:56 2016 +0200
@@ -869,6 +869,33 @@
             '  </ns0:section>\n'
             '</ns0:body>')
 
+    def test_strip_namespaces(self):
+        elem = ET.XML(SAMPLE_XML_NS)
+        elem.set('nons', 'attribute 1 without ns')
+        elem.set('{http://effbot.org/ns}withns', 'attribute 2 with ns')
+        elem[-1].set('{http://effbot.org/ns}yesns', 'attribute 3 with ns')
+
+        self.assertEqual(elem.tag, '{http://effbot.org/ns}body')
+        self.assertEqual(elem[0].tag, '{http://effbot.org/ns}tag')
+        self.assertEqual(elem[-1].tag, '{http://effbot.org/ns}section')
+        self.assertEqual(elem[-1][0].tag, '{http://effbot.org/ns}tag')
+
+        self.assertEqual(elem.get('nons'), 'attribute 1 without ns')
+        self.assertEqual(elem.get('{http://effbot.org/ns}withns'), 'attribute 2 with ns')
+        self.assertEqual(elem[-1].get('{http://effbot.org/ns}yesns'), 'attribute 3 with ns')
+
+        ET.strip_namespaces(elem)
+        self.assertEqual(elem.tag, 'body')
+        self.assertEqual(elem[0].tag, 'tag')
+        self.assertEqual(elem[-1].tag, 'section')
+        self.assertEqual(elem[-1][0].tag, 'tag')
+
+        self.assertEqual(elem.get('nons'), 'attribute 1 without ns')
+        self.assertEqual(elem.get('withns'), 'attribute 2 with ns')
+        self.assertEqual(elem[-1].get('yesns'), 'attribute 3 with ns')
+        self.assertIsNone(elem.get('{http://effbot.org/ns}withns'))
+        self.assertIsNone(elem[-1].get('{http://effbot.org/ns}yesns'))
+
     def test_qname(self):
         # Test QName handling.
 
diff -r da9898e7e90d Lib/xml/etree/ElementTree.py
--- a/Lib/xml/etree/ElementTree.py	Wed Jul 27 16:59:22 2016 +0200
+++ b/Lib/xml/etree/ElementTree.py	Wed Jul 27 19:56:56 2016 +0200
@@ -536,6 +536,24 @@
             return self.text == other.text
         return self.text == other
 
+
+def strip_namespaces(tree):
+    """Remove all namespaces from tags and attributes in place.
+
+    Leaves only the local names in the subtree.
+    """
+    for el in tree.iter():
+        tag = el.tag
+        if tag and isinstance(tag, str) and tag[0] == '{':
+            el.tag = tag.partition('}')[2]
+        attrib = el.attrib
+        if attrib:
+            for name, value in list(attrib.items()):
+                if name and isinstance(name, str) and name[0] == '{':
+                    del attrib[name]
+                    attrib[name.partition('}')[2]] = value
+
+
 # --------------------------------------------------------------------