diff --git a/httpie/client.py b/httpie/client.py
index 6eef07b7..5102ce46 100644
--- a/httpie/client.py
+++ b/httpie/client.py
@@ -38,6 +38,15 @@ def get_response(args, config_dir):
     return response
 
 
+def encode_headers(headers):
+    # This allows for unicode headers which is non-standard but practical.
+    # See: https://github.com/jkbr/httpie/issues/212
+    return dict(
+        (name, value.encode('utf8') if isinstance(value, str) else value)
+        for name, value in headers.items()
+    )
+
+
 def get_requests_kwargs(args):
     """Translate our `args` into `requests.request` keyword arguments."""
 
@@ -80,18 +89,11 @@ def get_requests_kwargs(args):
         if args.certkey:
             cert = (cert, args.certkey)
 
-    # This allows for unicode headers which is non-standard but practical.
-    # See: https://github.com/jkbr/httpie/issues/212
-    headers = dict(
-        (name, value.encode('utf8') if isinstance(value, str) else value)
-        for name, value in args.headers.items()
-    )
-
     kwargs = {
         'stream': True,
         'method': args.method.lower(),
         'url': args.url,
-        'headers': headers,
+        'headers': encode_headers(args.headers),
         'data': args.data,
         'verify': {
             'yes': True,
diff --git a/httpie/plugins/builtin.py b/httpie/plugins/builtin.py
index 12038aea..92b2f302 100644
--- a/httpie/plugins/builtin.py
+++ b/httpie/plugins/builtin.py
@@ -19,11 +19,16 @@ class HTTPBasicAuth(requests.auth.HTTPBasicAuth):
         See https://github.com/jkbr/httpie/issues/212
 
         """
-        credentials = u'%s:%s' % (self.username, self.password)
-        token = b64encode(credentials.encode('utf8')).strip().decode('latin1')
-        r.headers['Authorization'] = 'Basic %s' % token
+        r.headers['Authorization'] = type(self).make_header(
+            self.username, self.password).encode('latin1')
         return r
 
+    @staticmethod
+    def make_header(username, password):
+        credentials = u'%s:%s' % (username, password)
+        token = b64encode(credentials.encode('utf8')).strip().decode('latin1')
+        return 'Basic %s' % token
+
 
 class BasicAuthPlugin(BuiltinAuthPlugin):
 
diff --git a/httpie/sessions.py b/httpie/sessions.py
index 7aa370dc..2404e234 100644
--- a/httpie/sessions.py
+++ b/httpie/sessions.py
@@ -27,6 +27,7 @@ def get_response(session_name, requests_kwargs, config_dir, args,
     aspects of the session to the request.
 
     """
+    from .client import encode_headers
     if os.path.sep in session_name:
         path = os.path.expanduser(session_name)
     else:
@@ -49,8 +50,9 @@ def get_response(session_name, requests_kwargs, config_dir, args,
 
     request_headers = requests_kwargs.get('headers', {})
 
-    requests_kwargs['headers'] = dict(session.headers)
-    requests_kwargs['headers'].update(request_headers)
+    merged_headers = dict(session.headers)
+    merged_headers.update(request_headers)
+    requests_kwargs['headers'] = encode_headers(merged_headers)
 
     session.update_headers(request_headers)
 
diff --git a/tests/test_sessions.py b/tests/test_sessions.py
index efb02d38..2ef4bafd 100644
--- a/tests/test_sessions.py
+++ b/tests/test_sessions.py
@@ -1,5 +1,7 @@
+# coding=utf-8
 import os
 import shutil
+from httpie.plugins.builtin import HTTPBasicAuth
 
 from tests import TestEnvironment, mk_config_dir, http, httpbin, HTTP_OK
 
@@ -121,3 +123,17 @@ class TestSession(SessionTestBase):
                   env=self.env())
         assert HTTP_OK in r2
         assert r2.json['headers']['Foo'] == 'Bar'
+
+    def test_session_unicode(self):
+        UNICODE = u'太陽'
+        r1 = http('--session=test', '--auth', u'test:' + UNICODE,
+                  'GET', httpbin('/get'),
+                  u'Test:%s' % UNICODE,
+                  env=self.env())
+        assert HTTP_OK in r1
+
+        r2 = http('--session=test', 'GET', httpbin('/get'), env=self.env())
+        assert HTTP_OK in r2
+        assert (r2.json['headers']['Authorization']
+                == HTTPBasicAuth.make_header(u'test', UNICODE))
+        assert r2.json['headers']['Test'] == UNICODE