diff --git a/README.md b/README.md
index f46d0e74..5342d198 100644
--- a/README.md
+++ b/README.md
@@ -79,6 +79,7 @@ Included service implementations
     - Reddit
     - RunKeeper
     - Salesforce
+    - Slack
     - SoundCloud
     - Spotify
     - Strava
diff --git a/examples/provider/slack.php b/examples/provider/slack.php
new file mode 100644
index 00000000..b25ec5f3
--- /dev/null
+++ b/examples/provider/slack.php
@@ -0,0 +1,54 @@
+<?php
+
+use OAuth\Common\Consumer\Credentials;
+use OAuth\Common\Http\Client\CurlClient;
+use OAuth\Common\Http\Exception\TokenResponseException;
+use OAuth\Common\Storage\Session;
+use OAuth\Helper\Example;
+use OAuth\OAuth2\Service\Slack;
+
+require_once __DIR__.'/../bootstrap.php';
+
+$helper = new Example();
+$storage = new Session();
+$client = new CurlClient();
+
+// actions to perform on your slack workspace :
+// go to https://api.slack.com/apps and create an app
+// under OAuth & Permissions set http://localhost:8000/provider/slack.php as reply url
+// under Scopes add identity.basic and identity.email to recover user's data
+
+
+if (empty($_GET)) {
+    echo $helper->getContent();
+} elseif (!empty($_GET['key']) && !empty($_GET['secret']) && $_GET['oauth'] !== 'redirect') {
+    echo $helper->getHeader();
+    try {
+        $credentials = new Credentials($_GET['key'], $_GET['secret'], $helper->getCurrentUrl());
+        $slack =new Slack($credentials, $client, $storage,  array(Slack::SCOPE_ID_BASIC, Slack::SCOPE_ID_EMAIL));
+
+        echo '<a href="'.$slack->getAuthorizationUri().'">get access token</a>';
+    } catch (\Exception $exception) {
+        $helper->getErrorMessage($exception);
+    }
+    echo $helper->getFooter();
+} elseif (!empty($_GET['code'])) {
+    $credentials = new Credentials($_GET['key'], $_GET['secret'], $helper->getCurrentUrl());
+    $slack =new Slack($credentials, $client, $storage,  array(Slack::SCOPE_ID_BASIC, Slack::SCOPE_ID_EMAIL));
+
+    echo $helper->getHeader();
+    try {
+        $token = $slack->requestAccessToken($_GET['code']);
+        echo 'access token: ' . $token->getAccessToken() . '<br>';
+        
+        $result = json_decode($slack->request('users.identity'), true);
+        //    Show some of the resultant data
+        echo 'Your slack name is ' . $result['user']['name'] . ' and your email is ' . $result['user']['email'] . '<br>';
+        echo 'You logged in with slack workspace id = ' . $result['team']['id'] . '<br>';
+        echo "Full response :<pre>" . json_encode($result, JSON_PRETTY_PRINT) . '</pre>';        
+
+    } catch (TokenResponseException $exception) {
+        $helper->getErrorMessage($exception);
+    }
+    echo $helper->getFooter();
+}
diff --git a/src/OAuth/OAuth2/Service/Slack.php b/src/OAuth/OAuth2/Service/Slack.php
new file mode 100644
index 00000000..0733aa96
--- /dev/null
+++ b/src/OAuth/OAuth2/Service/Slack.php
@@ -0,0 +1,96 @@
+<?php
+
+namespace OAuth\OAuth2\Service;
+
+use OAuth\OAuth2\Token\StdOAuth2Token;
+use OAuth\Common\Http\Exception\TokenResponseException;
+use OAuth\Common\Http\Uri\Uri;
+use OAuth\Common\Consumer\CredentialsInterface;
+use OAuth\Common\Http\Client\ClientInterface;
+use OAuth\Common\Storage\TokenStorageInterface;
+use OAuth\Common\Http\Uri\UriInterface;
+
+/**
+ * Slack service.
+ *
+ * @author Christophe Garde <christophe.garde@gmail.com>
+ * @link https://api.slack.com/#read_the_docs
+ */
+class Slack extends AbstractService
+{
+    // Basic
+    const SCOPE_ID_EMAIL                       = 'identity.email';
+    const SCOPE_ID_BASIC                       = 'identity.basic';
+   
+    public function __construct(
+        CredentialsInterface $credentials,
+        ClientInterface $httpClient,
+        TokenStorageInterface $storage,
+        $scopes = array(),
+        UriInterface $baseApiUri = null
+    ) {
+        parent::__construct($credentials, $httpClient, $storage, $scopes, $baseApiUri, $stateParameterInAutUrl = true);
+      
+
+        if (null === $baseApiUri) {
+            $this->baseApiUri = new Uri('https://slack.com/api/');
+        }
+    }
+    
+    
+    /**
+     * {@inheritdoc}
+     */
+    public function getAuthorizationUri(array $additionalParameters = array()){
+        // replace scope by user_scope
+        // this is a bit ugly, but still looks better than overriding the whole function :)
+        return str_replace('&scope=','&scope=&user_scope=',parent::getAuthorizationUri($additionalParameters));
+    }
+    
+    /**
+     * {@inheritdoc}
+     */
+    public function getAuthorizationEndpoint()
+    {
+        return new Uri('https://slack.com/oauth/v2/authorize');
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getAccessTokenEndpoint()
+    {
+        return new Uri('https://slack.com/api/oauth.v2.access');
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function getAuthorizationMethod()
+    {
+        return static::AUTHORIZATION_METHOD_HEADER_BEARER;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function parseAccessTokenResponse($responseBody)
+    {
+        $data = json_decode($responseBody, true);
+        if (null === $data || !is_array($data)) {
+            throw new TokenResponseException('Unable to parse response.');
+        } elseif (isset($data['error'])) {
+            throw new TokenResponseException('Error in retrieving token: "' . $data['error'] . '"');
+        }
+      
+        $token = new StdOAuth2Token();
+        $token->setAccessToken($data['authed_user']['access_token']);
+        $token->setEndOfLife(StdOAuth2Token::EOL_NEVER_EXPIRES);
+
+        unset($data['authed_user']['access_token']);
+
+        $token->setExtraParams(array($data['authed_user']));
+        return $token;
+    }
+
+}
diff --git a/tests/Unit/OAuth2/Service/SlackTest.php b/tests/Unit/OAuth2/Service/SlackTest.php
new file mode 100644
index 00000000..df0aaf13
--- /dev/null
+++ b/tests/Unit/OAuth2/Service/SlackTest.php
@@ -0,0 +1,198 @@
+<?php
+
+namespace OAuthTest\Unit\OAuth2\Service;
+
+use OAuth\Common\Token\TokenInterface;
+use OAuth\OAuth2\Token\StdOAuth2Token;
+use OAuth\OAuth2\Service\Slack;
+use PHPUnit\Framework\TestCase;
+
+class SlackTest extends TestCase
+{
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     */
+    public function testConstructCorrectInterfaceWithoutCustomUri(): void
+    {
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface'),
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        self::assertInstanceOf('\\OAuth\\OAuth2\\Service\\ServiceInterface', $service);
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     */
+    public function testConstructCorrectInstanceWithoutCustomUri(): void
+    {
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface'),
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        self::assertInstanceOf('\\OAuth\\OAuth2\\Service\\AbstractService', $service);
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     */
+    public function testConstructCorrectInstanceWithCustomUri(): void
+    {
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface'),
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface'),
+            [],
+            $this->createMock('\\OAuth\\Common\\Http\\Uri\\UriInterface')
+        );
+
+        self::assertInstanceOf('\\OAuth\\OAuth2\\Service\\AbstractService', $service);
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::getAuthorizationEndpoint
+     */
+    public function testGetAuthorizationEndpoint(): void
+    {
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface'),
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        self::assertSame(
+            'https://slack.com/oauth/v2/authorize',
+            $service->getAuthorizationEndpoint()->getAbsoluteUri()
+        );
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::getAccessTokenEndpoint
+     */
+    public function testGetAccessTokenEndpoint(): void
+    {
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface'),
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        self::assertSame(
+            'https://slack.com/api/oauth.v2.access',
+            $service->getAccessTokenEndpoint()->getAbsoluteUri()
+        );
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::getAuthorizationMethod
+     */
+    public function testGetAuthorizationMethod(): void
+    {
+        $client = $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface');
+        $client->expects(self::once())->method('retrieveResponse')->willReturnArgument(2);
+
+        $token = $this->createMock('\\OAuth\\OAuth2\\Token\\TokenInterface');
+        $token->expects(self::once())->method('getEndOfLife')->willReturn(TokenInterface::EOL_NEVER_EXPIRES);
+        $token->expects(self::once())->method('getAccessToken')->willReturn('foo');
+
+        $storage = $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface');
+        $storage->expects(self::once())->method('retrieveAccessToken')->willReturn($token);
+
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $client,
+            $storage
+        );
+
+        $headers = $service->request('https://pieterhordijk.com/my/awesome/path');
+        self::assertArrayHasKey('Authorization', $headers);
+        self::assertTrue(in_array('Bearer foo', $headers, true));
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::parseAccessTokenResponse
+     */
+    public function testParseAccessTokenResponseThrowsExceptionOnNulledResponse(): void
+    {
+        $client = $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface');
+        $client->expects(self::once())->method('retrieveResponse')->willReturn(null);
+
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $client,
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        $this->expectException('\\OAuth\\Common\\Http\\Exception\\TokenResponseException');
+
+        $service->requestAccessToken('foo');
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::parseAccessTokenResponse
+     */
+    public function testParseAccessTokenResponseThrowsExceptionOnErrorDescription(): void
+    {
+        $client = $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface');
+        $client->expects(self::once())->method('retrieveResponse')->willReturn('error_description=some_error');
+
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $client,
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        $this->expectException('\\OAuth\\Common\\Http\\Exception\\TokenResponseException');
+
+        $service->requestAccessToken('foo');
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::parseAccessTokenResponse
+     */
+    public function testParseAccessTokenResponseThrowsExceptionOnError(): void
+    {
+        $client = $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface');
+        $client->expects(self::once())->method('retrieveResponse')->willReturn('error=some_error');
+
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $client,
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        $this->expectException('\\OAuth\\Common\\Http\\Exception\\TokenResponseException');
+
+        $service->requestAccessToken('foo');
+    }
+
+    /**
+     * @covers \OAuth\OAuth2\Service\Slack::__construct
+     * @covers \OAuth\OAuth2\Service\Slack::parseAccessTokenResponse
+     */
+    public function testParseAccessTokenResponseValidWithoutRefreshToken(): void
+    {
+        
+        $client = $this->createMock('\\OAuth\\Common\\Http\\Client\\ClientInterface');
+        $client->expects(self::once())->method('retrieveResponse')->willReturn('{"access_token":"foo","expires_in":"bar"}');
+
+        $service = new Slack(
+            $this->createMock('\\OAuth\\Common\\Consumer\\CredentialsInterface'),
+            $client,
+            $this->createMock('\\OAuth\\Common\\Storage\\TokenStorageInterface')
+        );
+
+        self::assertInstanceOf('\\OAuth\\OAuth2\\Token\\StdOAuth2Token', $service->requestAccessToken('foo'));
+
+    }
+}