diff --git a/.travis.yml b/.travis.yml
index 09ef823f..1a904b89 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,3 +15,7 @@ script:
     - py.test --cov jupyterhub jupyterhub/tests -v
 after_success:
     - codecov
+matrix:
+  include:
+    - python: 3.5
+      env: JUPYTERHUB_TEST_SUBDOMAIN_HOST=http://127.0.0.1.xip.io:8000
diff --git a/jupyterhub/apihandlers/base.py b/jupyterhub/apihandlers/base.py
index ce422009..a63233b2 100644
--- a/jupyterhub/apihandlers/base.py
+++ b/jupyterhub/apihandlers/base.py
@@ -86,7 +86,7 @@ class APIHandler(BaseHandler):
         model = {
             'name': user.name,
             'admin': user.admin,
-            'server': user.server.base_url if user.running else None,
+            'server': user.url if user.running else None,
             'pending': None,
             'last_activity': user.last_activity.isoformat(),
         }
diff --git a/jupyterhub/apihandlers/proxy.py b/jupyterhub/apihandlers/proxy.py
index 4d17b8d9..54d75500 100644
--- a/jupyterhub/apihandlers/proxy.py
+++ b/jupyterhub/apihandlers/proxy.py
@@ -28,7 +28,7 @@ class ProxyAPIHandler(APIHandler):
     @gen.coroutine
     def post(self):
         """POST checks the proxy to ensure"""
-        yield self.proxy.check_routes()
+        yield self.proxy.check_routes(self.users)
         
     
     @admin_only
@@ -59,7 +59,7 @@ class ProxyAPIHandler(APIHandler):
             self.proxy.auth_token = model['auth_token']
         self.db.commit()
         self.log.info("Updated proxy at %s", server.bind_url)
-        yield self.proxy.check_routes()
+        yield self.proxy.check_routes(self.users)
         
 
 
diff --git a/jupyterhub/app.py b/jupyterhub/app.py
index c606c07e..ec944acd 100644
--- a/jupyterhub/app.py
+++ b/jupyterhub/app.py
@@ -16,6 +16,7 @@ from datetime import datetime
 from distutils.version import LooseVersion as V
 from getpass import getuser
 from subprocess import Popen
+from urllib.parse import urlparse
 
 if sys.version_info[:2] < (3,3):
     raise ValueError("Python < 3.3 not supported: %s" % sys.version)
@@ -230,8 +231,21 @@ class JupyterHub(Application):
         """
     )
     ip = Unicode('', config=True,
-        help="The public facing ip of the proxy"
+        help="The public facing ip of the whole application (the proxy)"
     )
+    
+    subdomain_host = Unicode('', config=True,
+        help="""The public-facing host (domain[:port]) on which the Hub will run.
+        
+        Only used when subdomains are involved.
+        """
+    )
+    def _subdomain_host_changed(self, name, old, new):
+        if new and '://' not in new:
+            # host should include '://'
+            # if not specified, assume https: You have to be really explicit about HTTP!
+            self.subdomain_host = 'https://' + new
+    
     port = Integer(8000, config=True,
         help="The public facing port of the proxy"
     )
@@ -248,6 +262,18 @@ class JupyterHub(Application):
         help="Supply extra arguments that will be passed to Jinja environment."
     )
     
+    use_subdomains = Bool(False, config=True,
+        help="""Run single-user servers on subdomains.
+        
+        Provides additional cross-site protections for client-side js.
+        
+        Requires <username>.hub.domain.tld to resolve to the same host as hub.domain.tld.
+        
+        In general, this is most easily achieved with wildcard DNS.
+        
+        When using SSL (i.e. always) this also requires a wildcard cert.
+        """)
+    
     proxy_cmd = Command('configurable-http-proxy', config=True,
         help="""The command to start the http proxy.
         
@@ -288,7 +314,6 @@ class JupyterHub(Application):
     hub_ip = Unicode('127.0.0.1', config=True,
         help="The ip for this process"
     )
-    
     hub_prefix = URLPrefix('/hub/', config=True,
         help="The prefix for the hub server. Must not be '/'"
     )
@@ -574,11 +599,15 @@ class JupyterHub(Application):
             q = self.db.query(orm.Hub)
             assert q.count() <= 1
             self._local.hub = q.first()
+            if self.use_subdomains and self._local.hub:
+                self._local.hub.host = self.subdomain_host
         return self._local.hub
     
     @hub.setter
     def hub(self, hub):
         self._local.hub = hub
+        if hub and self.use_subdomains:
+            hub.host = self.subdomain_host
     
     @property
     def proxy(self):
@@ -631,6 +660,10 @@ class JupyterHub(Application):
             server.ip = self.hub_ip
             server.port = self.hub_port
             server.base_url = self.hub_prefix
+        if self.use_subdomains:
+            if not self.subdomain_host:
+                raise ValueError("Must specify subdomain_host when using subdomains."
+                " This should be the public domain[:port] of the Hub.")
 
         self.db.commit()
     
@@ -809,6 +842,8 @@ class JupyterHub(Application):
             '--api-port', str(self.proxy.api_server.port),
             '--default-target', self.hub.server.host,
         ]
+        if self.use_subdomains:
+            cmd.append('--host-routing')
         if self.debug_proxy:
             cmd.extend(['--log-level', 'debug'])
         if self.ssl_key:
@@ -867,7 +902,7 @@ class JupyterHub(Application):
         )
         yield self.start_proxy()
         self.log.info("Setting up routes on new proxy")
-        yield self.proxy.add_all_users()
+        yield self.proxy.add_all_users(self.users)
         self.log.info("New proxy back up, and good to go")
     
     def init_tornado_settings(self):
@@ -893,6 +928,8 @@ class JupyterHub(Application):
         else:
             version_hash=datetime.now().strftime("%Y%m%d%H%M%S"),
         
+        subdomain_host = self.subdomain_host
+        domain = urlparse(subdomain_host).hostname
         settings = dict(
             log_function=log_request,
             config=self.config,
@@ -915,6 +952,9 @@ class JupyterHub(Application):
             template_path=self.template_paths,
             jinja2_env=jinja_env,
             version_hash=version_hash,
+            use_subdomains=self.use_subdomains,
+            subdomain_host=subdomain_host,
+            domain=domain,
         )
         # allow configured settings to have priority
         settings.update(self.tornado_settings)
@@ -1051,7 +1091,7 @@ class JupyterHub(Application):
             user.last_activity = max(user.last_activity, dt)
 
         self.db.commit()
-        yield self.proxy.check_routes(routes)
+        yield self.proxy.check_routes(routes, self.users)
     
     @gen.coroutine
     def start(self):
@@ -1086,7 +1126,7 @@ class JupyterHub(Application):
             self.exit(1)
             return
         
-        loop.add_callback(self.proxy.add_all_users)
+        loop.add_callback(self.proxy.add_all_users, self.users)
         
         if self.proxy_process:
             # only check / restart the proxy if we started it in the first place.
diff --git a/jupyterhub/handlers/base.py b/jupyterhub/handlers/base.py
index 3759e037..376b1c9d 100644
--- a/jupyterhub/handlers/base.py
+++ b/jupyterhub/handlers/base.py
@@ -51,6 +51,14 @@ class BaseHandler(RequestHandler):
     def version_hash(self):
         return self.settings.get('version_hash', '')
     
+    @property
+    def use_subdomains(self):
+        return self.settings.get('use_subdomains', False)
+    
+    @property
+    def domain(self):
+        return self.settings['domain']
+    
     @property
     def db(self):
         return self.settings['db']
@@ -199,42 +207,44 @@ class BaseHandler(RequestHandler):
             user = self.get_current_user()
         else:
             user = self.find_user(name)
+        kwargs = {}
+        if self.use_subdomains:
+            kwargs['domain'] = self.domain
         if user and user.server:
-            self.clear_cookie(user.server.cookie_name, path=user.server.base_url)
-        self.clear_cookie(self.hub.server.cookie_name, path=self.hub.server.base_url)
+            self.clear_cookie(user.server.cookie_name, path=user.server.base_url, **kwargs)
+        self.clear_cookie(self.hub.server.cookie_name, path=self.hub.server.base_url, **kwargs)
+    
+    def _set_user_cookie(self, user, server):
+        # tornado <4.2 have a bug that consider secure==True as soon as
+        # 'secure' kwarg is passed to set_secure_cookie
+        if  self.request.protocol == 'https':
+            kwargs = {'secure': True}
+        else:
+            kwargs = {}
+        if self.use_subdomains:
+            kwargs['domain'] = self.domain
+        self.log.debug("Setting cookie for %s: %s, %s", user.name, server.cookie_name, kwargs)
+        self.set_secure_cookie(
+            server.cookie_name,
+            user.cookie_id,
+            path=server.base_url,
+            **kwargs
+        )
     
     def set_server_cookie(self, user):
         """set the login cookie for the single-user server"""
-        # tornado <4.2 have a bug that consider secure==True as soon as
-        # 'secure' kwarg is passed to set_secure_cookie
-        if  self.request.protocol == 'https':
-            kwargs = {'secure':True}
-        else:
-            kwargs = {}
-        self.set_secure_cookie(
-            user.server.cookie_name,
-            user.cookie_id,
-            path=user.server.base_url,
-            **kwargs
-        )
+        self._set_user_cookie(user, user.server)
     
     def set_hub_cookie(self, user):
         """set the login cookie for the Hub"""
-        # tornado <4.2 have a bug that consider secure==True as soon as
-        # 'secure' kwarg is passed to set_secure_cookie
-        if  self.request.protocol == 'https':
-            kwargs = {'secure':True}
-        else:
-            kwargs = {}
-        self.set_secure_cookie(
-            self.hub.server.cookie_name,
-            user.cookie_id,
-            path=self.hub.server.base_url,
-            **kwargs
-        )
+        self._set_user_cookie(user, self.hub.server)
     
     def set_login_cookie(self, user):
         """Set login cookies for the Hub and single-user server."""
+        if self.use_subdomains and not self.request.host.startswith(self.domain):
+            self.log.warning(
+                "Possibly setting cookie on wrong domain: %s != %s",
+                self.request.host, self.domain)
         # create and set a new cookie token for the single-user server
         if user.server:
             self.set_server_cookie(user)
@@ -472,6 +482,8 @@ class UserSpawnHandler(BaseHandler):
             self.set_login_cookie(current_user)
             without_prefix = self.request.uri[len(self.hub.server.base_url):]
             target = url_path_join(self.base_url, without_prefix)
+            if self.use_subdomains:
+                target = current_user.host + target
             self.redirect(target)
         else:
             # not logged in to the right user,
diff --git a/jupyterhub/handlers/pages.py b/jupyterhub/handlers/pages.py
index 6575d1a8..e82490c4 100644
--- a/jupyterhub/handlers/pages.py
+++ b/jupyterhub/handlers/pages.py
@@ -25,7 +25,7 @@ class RootHandler(BaseHandler):
         user = self.get_current_user()
         if user:
             if user.running:
-                url = user.server.base_url
+                url = user.url
                 self.log.debug("User is running: %s", url)
             else:
                 url = url_path_join(self.hub.server.base_url, 'home')
@@ -67,7 +67,7 @@ class SpawnHandler(BaseHandler):
         """GET renders form for spawning with user-specified options"""
         user = self.get_current_user()
         if user.running:
-            url = user.server.base_url
+            url = user.url
             self.log.debug("User is running: %s", url)
             self.redirect(url)
             return
@@ -84,7 +84,7 @@ class SpawnHandler(BaseHandler):
         """POST spawns with user-specified options"""
         user = self.get_current_user()
         if user.running:
-            url = user.server.base_url
+            url = user.url
             self.log.warning("User is already running: %s", url)
             self.redirect(url)
             return
@@ -101,7 +101,7 @@ class SpawnHandler(BaseHandler):
             self.finish(self._render_form(str(e)))
             return
         self.set_login_cookie(user)
-        url = user.server.base_url
+        url = user.url
         self.redirect(url)
 
 class AdminHandler(BaseHandler):
diff --git a/jupyterhub/orm.py b/jupyterhub/orm.py
index 96327a15..2a61b937 100644
--- a/jupyterhub/orm.py
+++ b/jupyterhub/orm.py
@@ -176,10 +176,10 @@ class Proxy(Base):
     def add_user(self, user, client=None):
         """Add a user's server to the proxy table."""
         self.log.info("Adding user %s to proxy %s => %s",
-            user.name, user.server.base_url, user.server.host,
+            user.name, user.proxy_path, user.server.host,
         )
         
-        yield self.api_request(user.server.base_url,
+        yield self.api_request(user.proxy_path,
             method='POST',
             body=dict(
                 target=user.server.host,
@@ -192,26 +192,11 @@ class Proxy(Base):
     def delete_user(self, user, client=None):
         """Remove a user's server to the proxy table."""
         self.log.info("Removing user %s from proxy", user.name)
-        yield self.api_request(user.server.base_url,
+        yield self.api_request(user.proxy_path,
             method='DELETE',
             client=client,
         )
     
-    @gen.coroutine
-    def add_all_users(self):
-        """Update the proxy table from the database.
-        
-        Used when loading up a new proxy.
-        """
-        db = inspect(self).session
-        futures = []
-        for user in db.query(User):
-            if (user.server):
-                futures.append(self.add_user(user))
-        # wait after submitting them all
-        for f in futures:
-            yield f
-
     @gen.coroutine
     def get_routes(self, client=None):
         """Fetch the proxy's routes"""
@@ -219,15 +204,32 @@ class Proxy(Base):
         return json.loads(resp.body.decode('utf8', 'replace'))
 
     @gen.coroutine
-    def check_routes(self, routes=None):
-        """Check that all users are properly"""
+    def add_all_users(self, user_dict):
+        """Update the proxy table from the database.
+        
+        Used when loading up a new proxy.
+        """
+        db = inspect(self).session
+        futures = []
+        for orm_user in db.query(User):
+            user = user_dict[orm_user]
+            if (user.server):
+                futures.append(self.add_user(user))
+        # wait after submitting them all
+        for f in futures:
+            yield f
+
+    @gen.coroutine
+    def check_routes(self, user_dict, routes=None):
+        """Check that all users are properly routed on the proxy"""
         if not routes:
             routes = yield self.get_routes()
 
         have_routes = { r['user'] for r in routes.values() if 'user' in r }
         futures = []
         db = inspect(self).session
-        for user in db.query(User).filter(User.server != None):
+        for orm_user in db.query(User).filter(User.server != None):
+            user = user_dict[orm_user]
             if user.server is None:
                 # This should never be True, but seems to be on rare occasion.
                 # catch filter bug, either in sqlalchemy or my understanding of its behavior
@@ -253,6 +255,7 @@ class Hub(Base):
     id = Column(Integer, primary_key=True)
     _server_id = Column(Integer, ForeignKey('servers.id'))
     server = relationship(Server, primaryjoin=_server_id == Server.id)
+    host = ''
     
     @property
     def api_url(self):
diff --git a/jupyterhub/spawner.py b/jupyterhub/spawner.py
index 14b5735a..b44fd434 100644
--- a/jupyterhub/spawner.py
+++ b/jupyterhub/spawner.py
@@ -199,6 +199,7 @@ class Spawner(LoggingConfigurable):
             '--port=%i' % self.user.server.port,
             '--cookie-name=%s' % self.user.server.cookie_name,
             '--base-url=%s' % self.user.server.base_url,
+            '--hub-host=%s' % self.hub.host,
             '--hub-prefix=%s' % self.hub.server.base_url,
             '--hub-api-url=%s' % self.hub.api_url,
             ]
diff --git a/jupyterhub/tests/mocking.py b/jupyterhub/tests/mocking.py
index 0b77fc73..0d2f6bef 100644
--- a/jupyterhub/tests/mocking.py
+++ b/jupyterhub/tests/mocking.py
@@ -1,7 +1,7 @@
 """mock utilities for testing"""
 
+import os
 import sys
-from datetime import timedelta
 from tempfile import NamedTemporaryFile
 import threading
 
@@ -13,10 +13,11 @@ from tornado import gen
 from tornado.concurrent import Future
 from tornado.ioloop import IOLoop
 
-from ..spawner import LocalProcessSpawner
 from ..app import JupyterHub
 from ..auth import PAMAuthenticator
 from .. import orm
+from ..spawner import LocalProcessSpawner
+from ..utils import url_path_join
 
 from pamela import PAMError
 
@@ -110,6 +111,12 @@ class MockHub(JupyterHub):
     db_file = None
     confirm_no_ssl = True
     
+    def _subdomain_host_default(self):
+        return os.environ.get('JUPYTERHUB_TEST_SUBDOMAIN_HOST', '')
+    
+    def _use_subdomains_default(self):
+        return bool(self.subdomain_host)
+    
     def _ip_default(self):
         return '127.0.0.1'
     
@@ -161,7 +168,8 @@ class MockHub(JupyterHub):
         self.db_file.close()
     
     def login_user(self, name):
-        r = requests.post(self.proxy.public_server.url + 'hub/login',
+        base_url = public_url(self)
+        r = requests.post(base_url + 'hub/login',
             data={
                 'username': name,
                 'password': name,
@@ -171,3 +179,21 @@ class MockHub(JupyterHub):
         assert r.cookies
         return r.cookies
 
+
+def public_host(app):
+    if app.use_subdomains:
+        return app.subdomain_host
+    else:
+        return app.proxy.public_server.host
+
+
+def public_url(app):
+    return public_host(app) + app.proxy.public_server.base_url
+
+
+def user_url(user, app):
+    if app.use_subdomains:
+        host = user.host
+    else:
+        host = public_host(app)
+    return host + user.server.base_url
diff --git a/jupyterhub/tests/test_api.py b/jupyterhub/tests/test_api.py
index 413ff913..db2c2a44 100644
--- a/jupyterhub/tests/test_api.py
+++ b/jupyterhub/tests/test_api.py
@@ -2,7 +2,6 @@
 
 import json
 import time
-from datetime import timedelta
 from queue import Queue
 from urllib.parse import urlparse
 
@@ -14,6 +13,7 @@ from .. import orm
 from ..user import User
 from ..utils import url_path_join as ujoin
 from . import mocking
+from .mocking import public_url, user_url
 
 
 def check_db_locks(func):
@@ -105,7 +105,7 @@ def test_auth_api(app):
 
 
 def test_referer_check(app, io_loop):
-    url = app.hub.server.url
+    url = ujoin(public_url(app), app.hub.server.base_url)
     host = urlparse(url).netloc
     user = find_user(app.db, 'admin')
     if user is None:
@@ -352,15 +352,19 @@ def test_spawn(app, io_loop):
     assert status is None
     
     assert user.server.base_url == '/user/%s' % name
-    r = requests.get(ujoin(app.proxy.public_server.url, user.server.base_url))
+    url = user_url(user, app)
+    print(url)
+    r = requests.get(url)
     assert r.status_code == 200
     assert r.text == user.server.base_url
 
-    r = requests.get(ujoin(app.proxy.public_server.url, user.server.base_url, 'args'))
+    r = requests.get(ujoin(url, 'args'))
     assert r.status_code == 200
     argv = r.json()
     for expected in ['--user=%s' % name, '--base-url=%s' % user.server.base_url]:
         assert expected in argv
+    if app.use_subdomains:
+        assert '--hub-host=%s' % app.subdomain_host in argv
     
     r = api_request(app, 'users', name, 'server', method='delete')
     assert r.status_code == 204
diff --git a/jupyterhub/tests/test_pages.py b/jupyterhub/tests/test_pages.py
index ba85ff26..607e825e 100644
--- a/jupyterhub/tests/test_pages.py
+++ b/jupyterhub/tests/test_pages.py
@@ -8,12 +8,11 @@ from ..utils import url_path_join as ujoin
 from .. import orm
 
 import mock
-from .mocking import FormSpawner
+from .mocking import FormSpawner, public_url, public_host, user_url
 from .test_api import api_request
 
-
 def get_page(path, app, **kw):
-    base_url = ujoin(app.proxy.public_server.host, app.hub.server.base_url)
+    base_url = ujoin(public_url(app), app.hub.server.base_url)
     print(base_url)
     return requests.get(ujoin(base_url, path), **kw)
 
@@ -22,15 +21,17 @@ def test_root_no_auth(app, io_loop):
     routes = io_loop.run_sync(app.proxy.get_routes)
     print(routes)
     print(app.hub.server)
-    r = requests.get(app.proxy.public_server.host)
+    url = public_url(app)
+    print(url)
+    r = requests.get(url)
     r.raise_for_status()
-    assert r.url == ujoin(app.proxy.public_server.host, app.hub.server.base_url, 'login')
+    assert r.url == ujoin(url, app.hub.server.base_url, 'login')
 
 def test_root_auth(app):
     cookies = app.login_user('river')
-    r = requests.get(app.proxy.public_server.host, cookies=cookies)
+    r = requests.get(public_url(app), cookies=cookies)
     r.raise_for_status()
-    assert r.url == ujoin(app.proxy.public_server.host, '/user/river')
+    assert r.url == user_url(app.users['river'], app)
 
 def test_home_no_auth(app):
     r = get_page('home', app, allow_redirects=False)
@@ -100,7 +101,7 @@ def test_spawn_page(app):
 
 def test_spawn_form(app, io_loop):
     with mock.patch.dict(app.users.settings, {'spawner_class': FormSpawner}):
-        base_url = ujoin(app.proxy.public_server.host, app.hub.server.base_url)
+        base_url = ujoin(public_url(app), app.hub.server.base_url)
         cookies = app.login_user('jones')
         orm_u = orm.User.find(app.db, 'jones')
         u = app.users[orm_u]
@@ -121,7 +122,7 @@ def test_spawn_form(app, io_loop):
 
 def test_spawn_form_with_file(app, io_loop):
     with mock.patch.dict(app.users.settings, {'spawner_class': FormSpawner}):
-        base_url = ujoin(app.proxy.public_server.host, app.hub.server.base_url)
+        base_url = ujoin(public_url(app), app.hub.server.base_url)
         cookies = app.login_user('jones')
         orm_u = orm.User.find(app.db, 'jones')
         u = app.users[orm_u]
@@ -149,7 +150,7 @@ def test_spawn_form_with_file(app, io_loop):
 
 
 def test_static_files(app):
-    base_url = ujoin(app.proxy.public_server.url, app.hub.server.base_url)
+    base_url = ujoin(public_url(app), app.hub.server.base_url)
     print(base_url)
     r = requests.get(ujoin(base_url, 'logo'))
     r.raise_for_status()
diff --git a/jupyterhub/tests/test_proxy.py b/jupyterhub/tests/test_proxy.py
index c5fc5a97..5245da37 100644
--- a/jupyterhub/tests/test_proxy.py
+++ b/jupyterhub/tests/test_proxy.py
@@ -4,6 +4,7 @@ import json
 import os
 from queue import Queue
 from subprocess import Popen
+from urllib.parse import urlparse
 
 from .. import orm
 from .mocking import MockHub
@@ -34,6 +35,8 @@ def test_external_proxy(request, io_loop):
         '--api-port', str(proxy_port),
         '--default-target', 'http://%s:%i' % (app.hub_ip, app.hub_port),
     ]
+    if app.use_subdomains:
+        cmd.append('--host-routing')
     proxy = Popen(cmd, env=env)
     def _cleanup_proxy():
         if proxy.poll() is None:
@@ -60,7 +63,11 @@ def test_external_proxy(request, io_loop):
     r.raise_for_status()
     
     routes = io_loop.run_sync(app.proxy.get_routes)
-    assert sorted(routes.keys()) == ['/', '/user/river']
+    user_path = '/user/river'
+    if app.use_subdomains:
+        domain = urlparse(app.subdomain_host).hostname
+        user_path = '/%s.%s' % (name, domain) + user_path
+    assert sorted(routes.keys()) == ['/', user_path]
     
     # teardown the proxy and start a new one in the same place
     proxy.terminate()
@@ -76,7 +83,7 @@ def test_external_proxy(request, io_loop):
     
     # check that the routes are correct
     routes = io_loop.run_sync(app.proxy.get_routes)
-    assert sorted(routes.keys()) == ['/', '/user/river']
+    assert sorted(routes.keys()) == ['/', user_path]
     
     # teardown the proxy again, and start a new one with different auth and port
     proxy.terminate()
@@ -90,7 +97,8 @@ def test_external_proxy(request, io_loop):
         '--api-port', str(proxy_port),
         '--default-target', 'http://%s:%i' % (app.hub_ip, app.hub_port),
     ]
-    
+    if app.use_subdomains:
+        cmd.append('--host-routing')
     proxy = Popen(cmd, env=env)
     wait_for_proxy()
     
@@ -113,7 +121,7 @@ def test_external_proxy(request, io_loop):
     
     # check that the routes are correct
     routes = io_loop.run_sync(app.proxy.get_routes)
-    assert sorted(routes.keys()) == ['/', '/user/river']
+    assert sorted(routes.keys()) == ['/', user_path]
 
 def test_check_routes(app, io_loop):
     proxy = app.proxy
@@ -123,13 +131,14 @@ def test_check_routes(app, io_loop):
     r.raise_for_status()
     zoe = orm.User.find(app.db, 'zoe')
     assert zoe is not None
+    zoe = app.users[zoe]
     before = sorted(io_loop.run_sync(app.proxy.get_routes))
-    assert '/user/zoe' in before
-    io_loop.run_sync(app.proxy.check_routes)
+    assert zoe.proxy_path in before
+    io_loop.run_sync(lambda : app.proxy.check_routes(app.users))
     io_loop.run_sync(lambda : proxy.delete_user(zoe))
     during = sorted(io_loop.run_sync(app.proxy.get_routes))
-    assert '/user/zoe' not in during
-    io_loop.run_sync(app.proxy.check_routes)
+    assert zoe.proxy_path not in during
+    io_loop.run_sync(lambda : app.proxy.check_routes(app.users))
     after = sorted(io_loop.run_sync(app.proxy.get_routes))
-    assert '/user/zoe' in after
+    assert zoe.proxy_path in after
     assert before == after
diff --git a/jupyterhub/user.py b/jupyterhub/user.py
index 7d963e04..fafd67ff 100644
--- a/jupyterhub/user.py
+++ b/jupyterhub/user.py
@@ -2,7 +2,7 @@
 # Distributed under the terms of the Modified BSD License.
 
 from datetime import datetime, timedelta
-from urllib.parse import quote
+from urllib.parse import quote, urlparse
 
 from tornado import gen
 from tornado.log import app_log
@@ -38,6 +38,12 @@ class UserDict(dict):
     def __getitem__(self, key):
         if isinstance(key, User):
             key = key.id
+        elif isinstance(key, str):
+            orm_user = self.db.query(orm.User).filter(orm.User.name==key).first()
+            if orm_user is None:
+                raise KeyError("No such user: %s" % name)
+            else:
+                key = orm_user
         if isinstance(key, orm.User):
             # users[orm_user] returns User(orm_user)
             orm_user = key
@@ -148,6 +154,41 @@ class User(HasTraits):
         """My name, escaped for use in URLs, cookies, etc."""
         return quote(self.name, safe='@')
     
+    @property
+    def proxy_path(self):
+        if self.settings.get('use_subdomains'):
+            return url_path_join('/' + self.domain, self.server.base_url)
+        else:
+            return self.server.base_url
+    
+    @property
+    def domain(self):
+        """Get the domain for my server."""
+        # FIXME: escaped_name probably isn't escaped enough in general for a domain fragment
+        return self.escaped_name + '.' + self.settings['domain']
+    
+    @property
+    def host(self):
+        """Get the *host* for my server (domain[:port])"""
+        # FIXME: escaped_name probably isn't escaped enough in general for a domain fragment
+        parsed = urlparse(self.settings['subdomain_host'])
+        h = '%s://%s.%s' % (parsed.scheme, self.escaped_name, parsed.netloc)
+        return h
+    
+    @property
+    def url(self):
+        """My URL
+        
+        Full name.domain/path if using subdomains, otherwise just my /base/url
+        """
+        if self.settings.get('use_subdomains'):
+            return '{host}{path}'.format(
+                host=self.host,
+                path=self.server.base_url,
+            )
+        else:
+            return self.server.base_url
+    
     @gen.coroutine
     def spawn(self, options=None):
         """Start the user's spawner"""
diff --git a/scripts/jupyterhub-singleuser b/scripts/jupyterhub-singleuser
index e82ac6ad..4ec76ed0 100755
--- a/scripts/jupyterhub-singleuser
+++ b/scripts/jupyterhub-singleuser
@@ -104,7 +104,9 @@ class JupyterHubLoginHandler(LoginHandler):
 
 class JupyterHubLogoutHandler(LogoutHandler):
     def get(self):
-        self.redirect(url_path_join(self.settings['hub_prefix'], 'logout'))
+        self.redirect(
+            self.settings['hub_host'] +
+            url_path_join(self.settings['hub_prefix'], 'logout'))
 
 
 # register new hub related command-line aliases
@@ -113,6 +115,7 @@ aliases.update({
     'user' : 'SingleUserNotebookApp.user',
     'cookie-name': 'SingleUserNotebookApp.cookie_name',
     'hub-prefix': 'SingleUserNotebookApp.hub_prefix',
+    'hub-host': 'SingleUserNotebookApp.hub_host',
     'hub-api-url': 'SingleUserNotebookApp.hub_api_url',
     'base-url': 'SingleUserNotebookApp.base_url',
 })
@@ -141,6 +144,7 @@ class SingleUserNotebookApp(NotebookApp):
         self.log.name = new
     cookie_name = Unicode(config=True)
     hub_prefix = Unicode(config=True)
+    hub_host = Unicode(config=True)
     hub_api_url = Unicode(config=True)
     aliases = aliases
     open_browser = False
@@ -194,22 +198,22 @@ class SingleUserNotebookApp(NotebookApp):
         s['user'] = self.user
         s['hub_api_key'] = env.pop('JPY_API_TOKEN')
         s['hub_prefix'] = self.hub_prefix
+        s['hub_host'] = self.hub_host
         s['cookie_name'] = self.cookie_name
-        s['login_url'] = self.hub_prefix
+        s['login_url'] = self.hub_host + self.hub_prefix
         s['hub_api_url'] = self.hub_api_url
-        s['csp_report_uri'] = url_path_join(self.hub_prefix, 'security/csp-report')
-        
+        s['csp_report_uri'] = self.hub_host + url_path_join(self.hub_prefix, 'security/csp-report')
         super(SingleUserNotebookApp, self).init_webapp()
         self.patch_templates()
     
     def patch_templates(self):
         """Patch page templates to add Hub-related buttons"""
         
-        self.jinja_template_vars['logo_url'] = url_path_join(self.hub_prefix, 'logo')
+        self.jinja_template_vars['logo_url'] = self.hub_host + url_path_join(self.hub_prefix, 'logo')
         env = self.web_app.settings['jinja2_env']
         
         env.globals['hub_control_panel_url'] = \
-            url_path_join(self.hub_prefix, 'home')
+            self.hub_host + url_path_join(self.hub_prefix, 'home')
         
         # patch jinja env loading to modify page template
         def get_page(name):