new file mode 100644
--- /dev/null
+++ b/markup/output.py
@@ -0,0 +1,199 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2006 Christopher Lenz
+# All rights reserved.
+#
+# This software is licensed as described in the file COPYING, which
+# you should have received as part of this distribution. The terms
+# are also available at http://trac.edgewall.com/license.html.
+#
+# This software consists of voluntary contributions made by many
+# individuals. For the exact contribution history, see the revision
+# history and logs, available at http://projects.edgewall.com/trac/.
+
+"""This module provides different kinds of serialization methods for XML event
+streams.
+"""
+
+try:
+    frozenset
+except NameError:
+    from sets import ImmutableSet as frozenset
+
+from markup.core import Markup, QName, Stream
+from markup.filters import WhitespaceFilter
+
+__all__ = ['Serializer', 'XMLSerializer', 'HTMLSerializer']
+
+
+class Serializer(object):
+    """Base class for serializers."""
+
+    def serialize(self, stream):
+        raise NotImplementedError
+
+
+class XMLSerializer(Serializer):
+    """Produces XML text from an event stream.
+    
+    >>> from markup.builder import tag
+    >>> elem = tag.DIV(tag.A(href='foo'), tag.BR, tag.HR(noshade=True))
+    >>> print ''.join(XMLSerializer().serialize(elem.generate()))
+    <div><a href="foo"/><br/><hr noshade="True"/></div>
+    """
+
+    def serialize(self, stream):
+        ns_attrib = []
+        ns_mapping = {}
+
+        stream = PushbackIterator(stream)
+        for kind, data, pos in stream:
+
+            if kind is Stream.DOCTYPE:
+                # FIXME: what if there's no system or public ID in the input?
+                yield Markup('<!DOCTYPE %s "%s" "%s">\n' % data)
+
+            elif kind is Stream.START_NS:
+                prefix, uri = data
+                if uri not in ns_mapping:
+                    ns_mapping[uri] = prefix
+                    if not prefix:
+                        ns_attrib.append((QName('xmlns'), uri))
+                    else:
+                        ns_attrib.append((QName('xmlns:%s' % prefix), uri))
+
+            elif kind is Stream.START:
+                tag, attrib = data
+
+                tagname = tag.localname
+                if tag.namespace:
+                    try:
+                        prefix = ns_mapping[tag.namespace]
+                        if prefix:
+                            tagname = prefix + ':' + tag.localname
+                    except KeyError:
+                        ns_attrib.append((QName('xmlns'), tag.namespace))
+                buf = ['<', tagname]
+
+                if ns_attrib:
+                    attrib.extend(ns_attrib)
+                    ns_attrib = []
+                for attr, value in attrib:
+                    attrname = attr.localname
+                    if attr.namespace:
+                        try:
+                            prefix = ns_mapping[attr.namespace]
+                        except KeyError:
+                            # FIXME: synthesize a prefix for the attribute?
+                            prefix = ''
+                        if prefix:
+                            attrname = prefix + ':' + attrname
+                    buf.append(' %s="%s"' % (attrname, Markup.escape(value)))
+
+                kind, data, pos = stream.next()
+                if kind is Stream.END:
+                    buf.append('/>')
+                else:
+                    buf.append('>')
+                    stream.pushback((kind, data, pos))
+
+                yield Markup(''.join(buf))
+
+            elif kind is Stream.END:
+                tag = data
+                tagname = tag.localname
+                if tag.namespace:
+                    prefix = ns_mapping[tag.namespace]
+                    if prefix:
+                        tagname = prefix + ':' + tag.localname
+                yield Markup('</%s>' % tagname)
+
+            elif kind is Stream.TEXT:
+                yield Markup.escape(data, quotes=False)
+
+
+class HTMLSerializer(Serializer):
+    """Produces HTML text from an event stream.
+    
+    >>> from markup.builder import tag
+    >>> elem = tag.DIV(tag.A(href='foo'), tag.BR, tag.HR(noshade=True))
+    >>> print ''.join(HTMLSerializer().serialize(elem.generate()))
+    <div><a href="foo"></a><br><hr noshade></div>
+    """
+
+    NAMESPACE = 'http://www.w3.org/1999/xhtml'
+
+    _EMPTY_ELEMS = frozenset(['area', 'base', 'basefont', 'br', 'col', 'frame',
+                              'hr', 'img', 'input', 'isindex', 'link', 'meta',
+                              'param'])
+    _BOOLEAN_ATTRS = frozenset(['selected', 'checked', 'compact', 'declare',
+                                'defer', 'disabled', 'ismap', 'multiple',
+                                'nohref', 'noresize', 'noshade', 'nowrap'])
+
+    def serialize(self, stream):
+        ns_mapping = {}
+
+        stream = PushbackIterator(stream)
+        for kind, data, pos in stream:
+
+            if kind is Stream.DOCTYPE:
+                yield Markup('<!DOCTYPE %s "%s" "%s">\n' % data)
+
+            elif kind is Stream.START_NS:
+                prefix, uri = data
+                if uri not in ns_mapping:
+                    ns_mapping[uri] = prefix
+
+            elif kind is Stream.START:
+                tag, attrib = data
+                if tag.namespace and tag.namespace != self.NAMESPACE:
+                    continue # not in the HTML namespace, so don't emit
+                buf = ['<', tag.localname]
+                for attr, value in attrib:
+                    if attr.namespace and attr.namespace != self.NAMESPACE:
+                        continue # not in the HTML namespace, so don't emit
+                    if attr.localname in self._BOOLEAN_ATTRS:
+                        if value:
+                            buf.append(' %s' % attr.localname)
+                    else:
+                        buf.append(' %s="%s"' % (attr.localname,
+                                                 Markup.escape(value)))
+
+                if tag.localname in self._EMPTY_ELEMS:
+                    kind, data, pos = stream.next()
+                    if kind is not Stream.END:
+                        stream.pushback((kind, data, pos))
+
+                yield Markup(''.join(buf + ['>']))
+
+            elif kind is Stream.END:
+                tag = data
+                if tag.namespace and tag.namespace != self.NAMESPACE:
+                    continue # not in the HTML namespace, so don't emit
+                yield Markup('</%s>' % tag.localname)
+
+            elif kind is Stream.TEXT:
+                yield Markup.escape(data, quotes=False)
+
+
+class PushbackIterator(object):
+    """A simple wrapper for iterators that allows pushing items back on the
+    queue via the `pushback()` method.
+    
+    That can effectively be used to peek at the next item."""
+    __slots__ = ['iterable', 'buf']
+
+    def __init__(self, iterable):
+        self.iterable = iter(iterable)
+        self.buf = []
+
+    def __iter__(self):
+        return self
+
+    def next(self):
+        if self.buf:
+            return self.buf.pop(0)
+        return self.iterable.next()
+
+    def pushback(self, item):
+        self.buf.append(item)