diff --git a/.travis.yml b/.travis.yml
index 0f7a315..3d02ebf 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -30,12 +30,12 @@ before_install:
 - docker run -d --publish=28015:28015 rethinkdb
 
 before_script:
-- pip install . pytest requests
+- pip install . pytest requests warcio
 
 script:
-- py.test -vv tests
-- py.test -vv --rethinkdb-servers=localhost tests
-- py.test -vv --rethinkdb-servers=localhost --rethinkdb-big-table tests
+- py.test -v tests
+- py.test -v --rethinkdb-servers=localhost tests
+- py.test -v --rethinkdb-servers=localhost --rethinkdb-big-table tests
 
 notifications:
   slack:
diff --git a/setup.py b/setup.py
index 4483f14..547e1fa 100755
--- a/setup.py
+++ b/setup.py
@@ -51,7 +51,7 @@ except:
 
 setuptools.setup(
         name='warcprox',
-        version='2.1b1.dev71',
+        version='2.1b1.dev72',
         description='WARC writing MITM HTTP/S proxy',
         url='https://github.com/internetarchive/warcprox',
         author='Noah Levitt',
diff --git a/tests/run-tests.sh b/tests/run-tests.sh
index 0c5b254..334cfc2 100755
--- a/tests/run-tests.sh
+++ b/tests/run-tests.sh
@@ -40,9 +40,9 @@ do
             && (cd /warcprox && git diff HEAD) | patch -p1 \
             && virtualenv -p $python /tmp/venv \
             && source /tmp/venv/bin/activate \
-            && pip --log-file /tmp/pip.log install . pytest requests \
-            && py.test -vv tests \
-            && py.test -vv --rethinkdb-servers=localhost tests \
-            && py.test -vv --rethinkdb-servers=localhost --rethinkdb-big-table tests"
+            && pip --log-file /tmp/pip.log install . pytest requests warcio \
+            && py.test -v tests \
+            && py.test -v --rethinkdb-servers=localhost tests \
+            && py.test -v --rethinkdb-servers=localhost --rethinkdb-big-table tests"
 done
 
diff --git a/tests/test_warcprox.py b/tests/test_warcprox.py
index c61f6d8..e4692cf 100755
--- a/tests/test_warcprox.py
+++ b/tests/test_warcprox.py
@@ -45,6 +45,7 @@ import signal
 from collections import Counter
 import socket
 import datetime
+import warcio.archiveiterator
 
 try:
     import http.server as http_server
@@ -79,7 +80,7 @@ def _send(self, data):
         logging.info('sending data from %s', repr(data))
     orig_send(self, data)
 ### uncomment this to block see raw requests going over the wire
-# http_client.HTTPConnection.send = _send
+http_client.HTTPConnection.send = _send
 
 logging.basicConfig(
         stream=sys.stdout, level=logging.INFO, # level=warcprox.TRACE,
@@ -1391,6 +1392,25 @@ def test_choose_a_port_for_me(service_registry):
         controller.stop.set()
         th.join()
 
+def test_via_response_header(warcprox_, http_daemon, archiving_proxies, playback_proxies):
+    url = 'http://localhost:%s/a/z' % http_daemon.server_port
+    response = requests.get(url, proxies=archiving_proxies)
+    assert response.headers['via'] == '1.1 warcprox'
+
+    playback_response = _poll_playback_until(
+            playback_proxies, url, status=200, timeout_sec=10)
+    assert response.status_code == 200
+    assert not 'via' in playback_response
+
+    warc = warcprox_.warc_writer_thread.writer_pool.default_warc_writer._fpath
+    with open(warc, 'rb') as f:
+        for record in warcio.archiveiterator.ArchiveIterator(f):
+            if record.rec_headers.get_header('warc-target-uri') == url:
+                if record.rec_type == 'response':
+                    assert not record.http_headers.get_header('via')
+                elif record.rec_type == 'request':
+                    assert record.http_headers.get_header('via') == '1.1 warcprox'
+
 if __name__ == '__main__':
     pytest.main()
 
diff --git a/warcprox/mitmproxy.py b/warcprox/mitmproxy.py
index 5f592e4..d69f26e 100644
--- a/warcprox/mitmproxy.py
+++ b/warcprox/mitmproxy.py
@@ -163,7 +163,9 @@ class ProxyingRecordingHTTPResponse(http_client.HTTPResponse):
 
         status_and_headers = 'HTTP/1.1 {} {}\r\n'.format(
                 self.status, self.reason)
-        for k,v in self.msg.items():
+        self.headers['Via'] = via_header_value(
+                self.headers.get('Via'), '%0.1f' % (self.version / 10))
+        for k,v in self.headers.items():
             if k.lower() not in (
                     'connection', 'proxy-connection', 'keep-alive',
                     'proxy-authenticate', 'proxy-authorization', 'upgrade',
@@ -174,6 +176,15 @@ class ProxyingRecordingHTTPResponse(http_client.HTTPResponse):
 
         self.recorder.payload_starts_now()
 
+def via_header_value(orig, request_version):
+    via = orig
+    if via:
+        via += ', '
+    else:
+        via = ''
+    via = via + '%s %s' % (request_version, 'warcprox')
+    return via
+
 class MitmProxyHandler(http_server.BaseHTTPRequestHandler):
     '''
     An http proxy implementation of BaseHTTPRequestHandler, that acts as a
@@ -356,6 +367,10 @@ class MitmProxyHandler(http_server.BaseHTTPRequestHandler):
                 'Proxy-Authenticate', 'Proxy-Authorization', 'Upgrade'):
             del self.headers[key]
 
+        self.headers['Via'] = via_header_value(
+                self.headers.get('Via'),
+                self.request_version.replace('HTTP/', ''))
+
         # Add headers to the request
         # XXX in at least python3.3 str(self.headers) uses \n not \r\n :(
         req_str += '\r\n'.join(