diff --git a/src/api/Api.js b/src/api/index.js
similarity index 100%
rename from src/api/Api.js
rename to src/api/index.js
diff --git a/src/auth/Auth.js b/src/auth/Auth.js
deleted file mode 100644
index 1da5c40..0000000
--- a/src/auth/Auth.js
+++ /dev/null
@@ -1,26 +0,0 @@
-import ClientCredentialsFlow from './ClientCredentialsFlow';
-import TokenFetcher from './TokenFetcher';
-
-/**
- * Implements various KKBOX OAuth 2.0 authorization flows.
- */
-export default class Auth {
-  /**
-   * Initialize the Auth object with client id and client secret.
-   *
-   * @param {string} clientID
-   * @param {string} clientSecret
-   * @example new Auth(clientID, clientSecret);
-   */
-  constructor(clientID, clientSecret) {
-    /**
-     * @type {TokenFetcher}
-     */
-    this.tokenFetcher = new TokenFetcher(clientID, clientSecret);
-
-    /**
-     * @type {ClientCredentialsFlow}
-     */
-    this.clientCredentialsFlow = new ClientCredentialsFlow(this.tokenFetcher);
-  }
-}
diff --git a/src/auth/ClientCredentialsFlow.js b/src/auth/ClientCredentialsFlow.js
deleted file mode 100644
index ffb301a..0000000
--- a/src/auth/ClientCredentialsFlow.js
+++ /dev/null
@@ -1,28 +0,0 @@
-/**
- * Implements the client credentials flow. Used for accessing APIs that don't need any KKBOX
- * user's personal data.
- * @see https://docs-en.kkbox.codes/docs/getting-started
- */
-export default class ClientCredentialsFlow {
-  /**
-   * @ignore
-   */
-  constructor(token) {
-    /**
-     * @ignore
-     */
-    this.token = token;
-  }
-
-  /**
-   * Fetch access token.
-   *
-   * @return {Promise}
-   * @example auth.clientCredentialsFlow.fetchAccessToken();
-   */
-  fetchAccessToken() {
-    return this.token.fetchAccessToken({
-      grant_type: 'client_credentials'
-    });
-  }
-}
diff --git a/src/auth/TokenFetcher.js b/src/auth/TokenFetcher.js
deleted file mode 100644
index a16a0d5..0000000
--- a/src/auth/TokenFetcher.js
+++ /dev/null
@@ -1,42 +0,0 @@
-import axios from 'axios';
-import { authError } from '../catchError';
-import querystring from 'querystring';
-import { Token as ENDPOINT_TOKEN } from '../Endpoint';
-
-/**
- * Fetches access token.
- */
-export default class TokenFetcher {
-  /**
-   * @ignore
-   */
-  constructor(clientID, clientSecret) {
-    /**
-     * @ignore
-     */
-    this.clientID = clientID;
-
-    /**
-     * @ignore
-     */
-    this.clientSecret = clientSecret;
-  }
-
-  /**
-   * Fetches access token.
-   *
-   * @param {object} params - Form data.
-   * @return {Promise}
-   */
-  fetchAccessToken(params) {
-    return axios
-      .post(ENDPOINT_TOKEN, querystring.stringify(params), {
-        auth: {
-          username: this.clientID,
-          password: this.clientSecret
-        },
-        headers: {}
-      })
-      .catch(authError);
-  }
-}
diff --git a/src/auth/index.js b/src/auth/index.js
new file mode 100644
index 0000000..fde197f
--- /dev/null
+++ b/src/auth/index.js
@@ -0,0 +1,42 @@
+import axios from 'axios';
+import { authError } from '../catchError';
+import { Token as ENDPOINT_TOKEN } from '../Endpoint';
+
+/**
+ * Implements various KKBOX OAuth 2.0 authorization flows.
+ */
+export default class Auth {
+  /**
+   * Initialize the Auth object with client id and client secret.
+   *
+   * @param {string} clientID
+   * @param {string} clientSecret
+   * @example new Auth(clientID, clientSecret);
+   */
+  constructor(clientID, clientSecret) {
+    this.clientID = clientID;
+    this.clientSecret = clientSecret;
+  }
+
+  /**
+   * Fetch access token.
+   *
+   * @return {Promise}
+   * @example auth.fetchAccessToken();
+   */
+  fetchAccessToken() {
+    return axios({
+      method: 'POST',
+      url: ENDPOINT_TOKEN,
+      headers: {
+        'content-type': 'application/x-www-form-urlencoded'
+      },
+      data: 'grant_type=client_credentials',
+      auth: {
+        username: this.clientID,
+        password: this.clientSecret
+      }
+    })
+    .catch(authError);
+  }
+}
diff --git a/src/index.js b/src/index.js
index 7127840..02cd786 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,2 +1,2 @@
-export { default as Auth } from './auth/Auth';
-export { default as Api } from './api/Api';
+export { default as Auth } from './auth';
+export { default as Api } from './api';
diff --git a/src/test/apitest.js b/src/test/apitest.js
index 9666f78..1e79bd5 100644
--- a/src/test/apitest.js
+++ b/src/test/apitest.js
@@ -12,19 +12,17 @@ import MoodStationFetcher from '../api/MoodStationFetcher';
 import GenreStationFetcher from '../api/GenreStationFetcher';
 import ChartFetcher from '../api/ChartFetcher';
 import TrackFetcher from '../api/TrackFetcher';
-import TokenFetcher from '../auth/TokenFetcher';
-import ClientCredentials from '../auth/ClientCredentialsFlow';
+import Auth from '../auth/';
 import { kkbox_sdk } from '../../client_secrets.json';
 const CLIENT_ID = kkbox_sdk.client_id;
 const CLIENT_SECRET = kkbox_sdk.client_secret;
 
 describe('Api Begin to Test', () => {
-  describe('ClientCredentials', () => {
+  describe('Auth', () => {
     describe('#fetch the access token()', () => {
       it('should fetch access token', () => {
-        const tokenFetcher = new TokenFetcher(CLIENT_ID, CLIENT_SECRET);
-        const clientCredentials = new ClientCredentials(tokenFetcher);
-        return clientCredentials.fetchAccessToken().then(
+        const auth = new Auth(CLIENT_ID, CLIENT_SECRET);
+        return auth.fetchAccessToken().then(
           response => {
             const access_token = response.data.access_token;
             access_token.should.be.ok;
diff --git a/src/test/authtest.js b/src/test/authtest.js
index 50d12af..6ac69b7 100644
--- a/src/test/authtest.js
+++ b/src/test/authtest.js
@@ -1,18 +1,16 @@
 import should from 'should';
-import TokenFetcher from '../auth/TokenFetcher';
-import ClientCredentialsFlow from '../auth/ClientCredentialsFlow';
+import Auth from '../auth/';
 import { kkbox_sdk } from '../../client_secrets.json';
 
 const CLIENT_ID = kkbox_sdk.client_id;
 const CLIENT_SECRET = kkbox_sdk.client_secret;
 
 describe('Auth Begin to Test', () => {
-  const tokenFetcher = new TokenFetcher(CLIENT_ID, CLIENT_SECRET);
+  const auth = new Auth(CLIENT_ID, CLIENT_SECRET);
   describe('clientCredentialsFlow', () => {
     describe('#fetchAccessToken()', () => {
       it('should get access token', () => {
-        const clientCredentialsFlow = new ClientCredentialsFlow(tokenFetcher);
-        return clientCredentialsFlow.fetchAccessToken().then(response => {
+        return auth.fetchAccessToken().then(response => {
           const access_token = response.data.access_token;
           access_token.should.be.ok;
         });
diff --git a/src/test/sdktest.js b/src/test/sdktest.js
index 0167c7b..d725a8f 100644
--- a/src/test/sdktest.js
+++ b/src/test/sdktest.js
@@ -9,7 +9,7 @@ describe('SDK Begin to Test', () => {
   describe('Auth', () => {
     it('should get access token', () => {
       const auth = new Auth(CLIENT_ID, CLIENT_SECRET);
-      return auth.clientCredentialsFlow.fetchAccessToken().then(response => {
+      return auth.fetchAccessToken().then(response => {
         describe('Api With Fake Token', () => {
           const api = new Api('FAKE_TOKEN', 'HK');
           describe('Property checking', () => {