diff --git a/libcomxml/core/__init__.py b/libcomxml/core/__init__.py
index d50e665..79214a2 100644
--- a/libcomxml/core/__init__.py
+++ b/libcomxml/core/__init__.py
@@ -76,7 +76,7 @@ class XmlField(Field):
     """Field with XML capabilities
     """
     def __init__(self, name, value=None, parent=None, attributes=None,
-                 rep=None):
+                 rep=None, namespace=None):
         """
         :param name: the name of the field super(Cabecera, self).__init__(name, root)
         :param value: the value of the field
@@ -86,6 +86,7 @@ def __init__(self, name, value=None, parent=None, attributes=None,
         """
         self.parent = parent
         self.xml_enc = get_xml_default_encoding()
+        self.namespace = namespace
 
         super(XmlField, self).__init__(name, value=value,
                                        attributes=attributes, rep=rep)
@@ -125,13 +126,16 @@ def element(self, parent=None):
         :param parent: an etree Element to be used as parent for this one
         """
         if parent is not None:
-            ele = etree.SubElement(parent, self.name, **self.attributes)
+            if self.namespace:
+                name = '{%s}%s' % (self.namespace, self.name)
+            else:
+                name = self.name
+            ele = etree.SubElement(parent, name, **self.attributes)
         else:
             ele = etree.Element(self.name, **self.attributes)
         ele = self._parse_value(ele)
         return ele
 
-
     def __str__(self):
         """Returns the XML repr of the field
 
@@ -230,7 +234,7 @@ def build_tree(self):
             return
         self.doc_root = self.root.element()
         for key in self.sorted_fields():
-            if not key in self._fields:
+            if key not in self._fields:
                 continue
             field = self._fields[key]
             if field != self.root:
diff --git a/tests/test_libcomxml.py b/tests/test_libcomxml.py
index 5c912bf..90b31ba 100644
--- a/tests/test_libcomxml.py
+++ b/tests/test_libcomxml.py
@@ -213,3 +213,67 @@ def __init__(self):
         l.build_tree()
 
         self.assertEqual(self.xml, str(l))
+
+
+class Namespaces(unittest.TestCase):
+    def setUp(self):
+        self.xml = "<?xml version='1.0' encoding='UTF-8'?>\n"
+        self.xml += "<rss "
+        self.xml += "xmlns:opensearch=\"http://a9.com/-/spec/opensearch/1.1/\" "
+        self.xml += "xmlns:atom=\"http://www.w3.org/2005/Atom\" "
+        self.xml += "version=\"2.0\">"
+        self.xml += "<channel><link>http://example.com/New+York+history</link>"
+        self.xml += "<atom:link "
+        self.xml += "href=\"http://example.com/opensearchdescription.xml\" "
+        self.xml += "rel=\"search\" "
+        self.xml += "type=\"application/opensearchdescription+xml\"/>"
+        self.xml += "<opensearch:totalResults>4230000</opensearch:totalResults>"
+        self.xml += "</channel>"
+        self.xml += "</rss>"
+
+    def test_namesapces_root(self):
+
+
+        NAMESPACES = {
+            'opensearch': 'http://a9.com/-/spec/opensearch/1.1/',
+            'atom': 'http://www.w3.org/2005/Atom'
+        }
+
+        class Channel(XmlModel):
+
+            _sort_order = ('link', 'atom_link', 'os_total_results')
+
+            def __init__(self):
+                self.channel = XmlField('channel')
+                self.link = XmlField('link')
+                self.atom_link = XmlField(
+                    'link', namespace=NAMESPACES['atom']
+                )
+                self.os_total_results = XmlField(
+                    'totalResults', namespace=NAMESPACES['opensearch']
+                )
+                super(Channel, self).__init__('Channel', 'channel', drop_empty=False)
+
+        class Rss(XmlModel):
+
+            _sort_order = ('channel', )
+
+            def __init__(self):
+                self.tag = XmlField('rss', attributes={
+                    'version': '2.0', 'nsmap': NAMESPACES
+                })
+                self.channel = Channel()
+                super(Rss, self).__init__('RSS', 'tag', drop_empty=False)
+
+        rss = Rss()
+        rss.channel.atom_link.attributes.update({
+            'rel': 'search',
+            'type': 'application/opensearchdescription+xml',
+            'href': 'http://example.com/opensearchdescription.xml'
+        })
+        rss.channel.feed({
+            'link': 'http://example.com/New+York+history',
+            'os_total_results': 4230000,
+        })
+        rss.build_tree()
+        self.assertEqual(self.xml, str(rss))