diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
index 181cd51b8f..322f926759 100644
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -47,6 +47,7 @@ phutil_register_library_map(array(
     'AphrontWebpageResponse' => 'aphront/response/webpage',
     'ConduitAPIMethod' => 'applications/conduit/method/base',
     'ConduitAPIRequest' => 'applications/conduit/protocol/request',
+    'ConduitAPI_conduit_connect_Method' => 'applications/conduit/method/conduit/connect',
     'ConduitAPI_differential_creatediff_Method' => 'applications/conduit/method/differential/creatediff',
     'ConduitAPI_file_upload_Method' => 'applications/conduit/method/file/upload',
     'ConduitException' => 'applications/conduit/protocol/exception',
@@ -148,6 +149,7 @@ phutil_register_library_map(array(
     'AphrontSideNavView' => 'AphrontView',
     'AphrontTableView' => 'AphrontView',
     'AphrontWebpageResponse' => 'AphrontResponse',
+    'ConduitAPI_conduit_connect_Method' => 'ConduitAPIMethod',
     'ConduitAPI_differential_creatediff_Method' => 'ConduitAPIMethod',
     'ConduitAPI_file_upload_Method' => 'ConduitAPIMethod',
     'DifferentialChangeset' => 'DifferentialDAO',
diff --git a/src/applications/conduit/controller/api/PhabricatorConduitAPIController.php b/src/applications/conduit/controller/api/PhabricatorConduitAPIController.php
index c259cf4551..e3bd8e0e5a 100644
--- a/src/applications/conduit/controller/api/PhabricatorConduitAPIController.php
+++ b/src/applications/conduit/controller/api/PhabricatorConduitAPIController.php
@@ -55,7 +55,7 @@ class PhabricatorConduitAPIController
       if (isset($_REQUEST['params']) && is_array($_REQUEST['params'])) {
         $params_post = $request->getArr('params');
         foreach ($params_post as $key => $value) {
-          $params_post[$key] = json_decode($value);
+          $params_post[$key] = json_decode($value, true);
         }
         $params = $params_post;
       } else {
@@ -63,7 +63,7 @@ class PhabricatorConduitAPIController
         if (!strlen($params_json)) {
           $params = array();
         } else {
-          $params = json_decode($params_json);
+          $params = json_decode($params_json, true);
           if (!is_array($params)) {
             throw new Exception(
               "Invalid parameter information was passed to method ".
diff --git a/src/applications/conduit/method/conduit/connect/ConduitAPI_conduit_connect_Method.php b/src/applications/conduit/method/conduit/connect/ConduitAPI_conduit_connect_Method.php
new file mode 100644
index 0000000000..daa12ac7bc
--- /dev/null
+++ b/src/applications/conduit/method/conduit/connect/ConduitAPI_conduit_connect_Method.php
@@ -0,0 +1,88 @@
+<?php
+
+/*
+ * Copyright 2011 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+class ConduitAPI_conduit_connect_Method extends ConduitAPIMethod {
+
+  public function getMethodDescription() {
+    return "Connect a session-based client.";
+  }
+
+  public function defineParamTypes() {
+    return array(
+      'client'              => 'required string',
+      'clientVersion'       => 'required int',
+      'clientDescription'   => 'optional string',
+      'user'                => 'optional string',
+    );
+  }
+
+  public function defineReturnType() {
+    return 'dict<string, any>';
+  }
+
+  public function defineErrorTypes() {
+    return array(
+      "ERR-BAD-VERSION" =>
+        "Client/server version mismatch. Update your client.",
+      "ERR-UNKNOWN-CLIENT" =>
+        "Client is unknown.",
+      "ERR-UPDATE-ARC" =>
+        "Arcanist is now open source! Update your scripts/aliases to use ".
+        "'/home/engshare/devtools/arcanist/bin/arc' if you're running from ".
+        "a Facebook host, or see ".
+        "<http://www.intern.facebook.com/intern/wiki/index.php/Arcanist> for ".
+        "laptop instructions.",
+    );
+  }
+
+  protected function execute(ConduitAPIRequest $request) {
+
+    $client = $request->getValue('client');
+    $client_version = (int)$request->getValue('clientVersion');
+    $client_description = (string)$request->getValue('clientDescription');
+
+    // Log the connection, regardless of the outcome of checks below.
+    $connection = new PhabricatorConduitConnectionLog();
+    $connection->setClient($client);
+    $connection->setClientVersion($client_version);
+    $connection->setClientDescription($client_description);
+    $connection->setUsername((string)$request->getValue('user'));
+    $connection->save();
+
+    switch ($client) {
+      case 'arc':
+        $server_version = 2;
+        switch ($client_version) {
+          case 1:
+            throw new ConduitException('ERR-UPDATE-ARC');
+          case $server_version:
+            break;
+          default:
+            throw new ConduitException('ERR-BAD-VERSION');
+        }
+        break;
+      default:
+        throw new ConduitException('ERR-UNKNOWN-CLIENT');
+    }
+
+    return array(
+      'connectionID' => $connection->getID(),
+    );
+  }
+
+}
diff --git a/src/applications/conduit/method/conduit/connect/__init__.php b/src/applications/conduit/method/conduit/connect/__init__.php
new file mode 100644
index 0000000000..5d3459f000
--- /dev/null
+++ b/src/applications/conduit/method/conduit/connect/__init__.php
@@ -0,0 +1,14 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('phabricator', 'applications/conduit/method/base');
+phutil_require_module('phabricator', 'applications/conduit/protocol/exception');
+phutil_require_module('phabricator', 'applications/conduit/storage/connectionlog');
+
+
+phutil_require_source('ConduitAPI_conduit_connect_Method.php');