diff --git a/buffet/buffet_config_unittest.cc b/buffet/buffet_config_unittest.cc
new file mode 100644
index 0000000..cec8bbe
--- /dev/null
+++ b/buffet/buffet_config_unittest.cc
@@ -0,0 +1,247 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "buffet/buffet_config.h"
+
+#include <base/bind.h>
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+#include "buffet/commands/unittest_utils.h"
+#include "buffet/storage_impls.h"
+
+using testing::_;
+
+namespace buffet {
+
+class BuffetConfigTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    EXPECT_CALL(*this, OnConfigChanged(_))
+        .Times(1);  // Called from AddOnChangedCallback
+
+    std::unique_ptr<StorageInterface> storage{new MemStorage};
+    storage_ = storage.get();
+    config_.reset(new BuffetConfig{std::move(storage)});
+
+    config_->AddOnChangedCallback(
+        base::Bind(&BuffetConfigTest::OnConfigChanged, base::Unretained(this)));
+  }
+
+  MOCK_METHOD1(OnConfigChanged, void(const BuffetConfig&));
+
+  StorageInterface* storage_{nullptr};
+  std::unique_ptr<BuffetConfig> config_;
+  const BuffetConfig default_{nullptr};
+};
+
+TEST_F(BuffetConfigTest, NoStorage) {
+  BuffetConfig config{nullptr};
+  BuffetConfig::Transaction change{&config};
+  change.Commit();
+}
+
+TEST_F(BuffetConfigTest, Defaults) {
+  EXPECT_EQ("58855907228.apps.googleusercontent.com", config_->client_id());
+  EXPECT_EQ("eHSAREAHrIqPsHBxCE9zPPBi", config_->client_secret());
+  EXPECT_EQ("AIzaSyDSq46gG-AxUnC3zoqD9COIPrjolFsMfMA", config_->api_key());
+  EXPECT_EQ("https://accounts.google.com/o/oauth2/", config_->oauth_url());
+  EXPECT_EQ("https://www.googleapis.com/clouddevices/v1/",
+            config_->service_url());
+  EXPECT_EQ("Chromium", config_->oem_name());
+  EXPECT_EQ("Brillo", config_->model_name());
+  EXPECT_EQ("AAAAA", config_->model_id());
+  EXPECT_EQ("vendor", config_->device_kind());
+  EXPECT_EQ(7000, config_->polling_period_ms());
+  EXPECT_EQ("Developer device", config_->name());
+  EXPECT_EQ("", config_->description());
+  EXPECT_EQ("", config_->location());
+  EXPECT_EQ("viewer", config_->local_anonymous_access_role());
+  EXPECT_TRUE(config_->local_pairing_enabled());
+  EXPECT_TRUE(config_->local_discovery_enabled());
+  EXPECT_EQ("", config_->device_id());
+  EXPECT_EQ("", config_->refresh_token());
+  EXPECT_EQ("", config_->robot_account());
+}
+
+TEST_F(BuffetConfigTest, LoadConfig) {
+  chromeos::KeyValueStore config_store;
+  config_store.SetString("client_id", "conf_client_id");
+  config_store.SetString("client_secret", "conf_client_secret");
+  config_store.SetString("api_key", "conf_api_key");
+  config_store.SetString("oauth_url", "conf_oauth_url");
+  config_store.SetString("service_url", "conf_service_url");
+  config_store.SetString("oem_name", "conf_oem_name");
+  config_store.SetString("model_name", "conf_model_name");
+  config_store.SetString("model_id", "ABCDE");
+  config_store.SetString("polling_period_ms", "12345");
+  config_store.SetString("name", "conf_name");
+  config_store.SetString("description", "conf_description");
+  config_store.SetString("location", "conf_location");
+  config_store.SetString("local_anonymous_access_role", "user");
+  config_store.SetBoolean("local_pairing_enabled", false);
+  config_store.SetBoolean("local_discovery_enabled", false);
+
+  // Following will be ignored.
+  config_store.SetString("device_kind", "conf_device_kind");
+  config_store.SetString("device_id", "conf_device_id");
+  config_store.SetString("refresh_token", "conf_refresh_token");
+  config_store.SetString("robot_account", "conf_robot_account");
+
+  EXPECT_CALL(*this, OnConfigChanged(_)).Times(1);
+  config_->Load(config_store);
+
+  EXPECT_EQ("conf_client_id", config_->client_id());
+  EXPECT_EQ("conf_client_secret", config_->client_secret());
+  EXPECT_EQ("conf_api_key", config_->api_key());
+  EXPECT_EQ("conf_oauth_url", config_->oauth_url());
+  EXPECT_EQ("conf_service_url", config_->service_url());
+  EXPECT_EQ("conf_oem_name", config_->oem_name());
+  EXPECT_EQ("conf_model_name", config_->model_name());
+  EXPECT_EQ("ABCDE", config_->model_id());
+  EXPECT_EQ("developmentBoard", config_->device_kind());
+  EXPECT_EQ(12345, config_->polling_period_ms());
+  EXPECT_EQ("conf_name", config_->name());
+  EXPECT_EQ("conf_description", config_->description());
+  EXPECT_EQ("conf_location", config_->location());
+  EXPECT_EQ("user", config_->local_anonymous_access_role());
+  EXPECT_FALSE(config_->local_pairing_enabled());
+  EXPECT_FALSE(config_->local_discovery_enabled());
+
+  // Not from config.
+  EXPECT_EQ(default_.device_id(), config_->device_id());
+  EXPECT_EQ(default_.refresh_token(), config_->refresh_token());
+  EXPECT_EQ(default_.robot_account(), config_->robot_account());
+
+  // Nothing should be saved yet.
+  EXPECT_JSON_EQ("{}", *storage_->Load());
+
+  BuffetConfig::Transaction change{config_.get()};
+  EXPECT_CALL(*this, OnConfigChanged(_)).Times(1);
+  change.Commit();
+
+  auto expected = R"({
+     'description': 'conf_description',
+     'device_id': '',
+     'local_anonymous_access_role': 'user',
+     'local_discovery_enabled': false,
+     'local_pairing_enabled': false,
+     'location': 'conf_location',
+     'name': 'conf_name',
+     'refresh_token': '',
+     'robot_account': ''
+  })";
+  EXPECT_JSON_EQ(expected, *storage_->Load());
+}
+
+TEST_F(BuffetConfigTest, LoadState) {
+  auto state = R"({
+     'description': 'state_description',
+     'device_id': 'state_device_id',
+     'local_anonymous_access_role': 'user',
+     'local_discovery_enabled': false,
+     'local_pairing_enabled': false,
+     'location': 'state_location',
+     'name': 'state_name',
+     'refresh_token': 'state_refresh_token',
+     'robot_account': 'state_robot_account'
+  })";
+  storage_->Save(*buffet::unittests::CreateDictionaryValue(state));
+
+  chromeos::KeyValueStore config_store;
+  EXPECT_CALL(*this, OnConfigChanged(_)).Times(1);
+  config_->Load(config_store);
+
+  // Clear storage.
+  storage_->Save(base::DictionaryValue());
+
+  EXPECT_EQ(default_.client_id(), config_->client_id());
+  EXPECT_EQ(default_.client_secret(), config_->client_secret());
+  EXPECT_EQ(default_.api_key(), config_->api_key());
+  EXPECT_EQ(default_.oauth_url(), config_->oauth_url());
+  EXPECT_EQ(default_.service_url(), config_->service_url());
+  EXPECT_EQ(default_.oem_name(), config_->oem_name());
+  EXPECT_EQ(default_.model_name(), config_->model_name());
+  EXPECT_EQ(default_.model_id(), config_->model_id());
+  EXPECT_EQ(default_.device_kind(), config_->device_kind());
+  EXPECT_EQ(default_.polling_period_ms(), config_->polling_period_ms());
+  EXPECT_EQ("state_name", config_->name());
+  EXPECT_EQ("state_description", config_->description());
+  EXPECT_EQ("state_location", config_->location());
+  EXPECT_EQ("user", config_->local_anonymous_access_role());
+  EXPECT_FALSE(config_->local_pairing_enabled());
+  EXPECT_FALSE(config_->local_discovery_enabled());
+  EXPECT_EQ("state_device_id", config_->device_id());
+  EXPECT_EQ("state_refresh_token", config_->refresh_token());
+  EXPECT_EQ("state_robot_account", config_->robot_account());
+
+  // Nothing should be saved yet.
+  EXPECT_JSON_EQ("{}", *storage_->Load());
+
+  BuffetConfig::Transaction change{config_.get()};
+  EXPECT_CALL(*this, OnConfigChanged(_)).Times(1);
+  change.Commit();
+
+  EXPECT_JSON_EQ(state, *storage_->Load());
+}
+
+TEST_F(BuffetConfigTest, Setters) {
+  BuffetConfig::Transaction change{config_.get()};
+
+  change.set_name("set_name");
+  EXPECT_EQ("set_name", config_->name());
+
+  change.set_description("set_description");
+  EXPECT_EQ("set_description", config_->description());
+
+  change.set_location("set_location");
+  EXPECT_EQ("set_location", config_->location());
+
+  change.set_local_anonymous_access_role("viewer");
+  EXPECT_EQ("viewer", config_->local_anonymous_access_role());
+
+  change.set_local_anonymous_access_role("none");
+  EXPECT_EQ("none", config_->local_anonymous_access_role());
+
+  change.set_local_anonymous_access_role("user");
+  EXPECT_EQ("user", config_->local_anonymous_access_role());
+
+  change.set_local_discovery_enabled(false);
+  EXPECT_FALSE(config_->local_discovery_enabled());
+
+  change.set_local_pairing_enabled(false);
+  EXPECT_FALSE(config_->local_pairing_enabled());
+
+  change.set_local_discovery_enabled(true);
+  EXPECT_TRUE(config_->local_discovery_enabled());
+
+  change.set_local_pairing_enabled(true);
+  EXPECT_TRUE(config_->local_pairing_enabled());
+
+  change.set_device_id("set_id");
+  EXPECT_EQ("set_id", config_->device_id());
+
+  change.set_refresh_token("set_token");
+  EXPECT_EQ("set_token", config_->refresh_token());
+
+  change.set_robot_account("set_account");
+  EXPECT_EQ("set_account", config_->robot_account());
+
+  EXPECT_CALL(*this, OnConfigChanged(_)).Times(1);
+  change.Commit();
+
+  auto expected = R"({
+    'description': 'set_description',
+    'device_id': 'set_id',
+    'local_anonymous_access_role': 'user',
+    'local_discovery_enabled': true,
+    'local_pairing_enabled': true,
+    'location': 'set_location',
+    'name': 'set_name',
+    'refresh_token': 'set_token',
+    'robot_account': 'set_account'
+  })";
+  EXPECT_JSON_EQ(expected, *storage_->Load());
+}
+}  // namespace buffet