diff --git a/spec/Authentication/BasicAuthSpec.php b/spec/Authentication/BasicAuthSpec.php
index 3729191..79aabaf 100644
--- a/spec/Authentication/BasicAuthSpec.php
+++ b/spec/Authentication/BasicAuthSpec.php
@@ -24,25 +24,11 @@ function it_has_a_username()
         $this->getUsername()->shouldReturn('john.doe');
     }
 
-    function it_accepts_a_username()
-    {
-        $this->setUsername('jane.doe');
-
-        $this->getUsername()->shouldReturn('jane.doe');
-    }
-
     function it_has_a_password()
     {
         $this->getPassword()->shouldReturn('secret');
     }
 
-    function it_accepts_a_password()
-    {
-        $this->setPassword('very_secret');
-
-        $this->getPassword()->shouldReturn('very_secret');
-    }
-
     function it_authenticates_a_request(RequestInterface $request, RequestInterface $newRequest)
     {
         $request->withHeader('Authorization', 'Basic '.base64_encode('john.doe:secret'))->willReturn($newRequest);
diff --git a/spec/Authentication/BearerSpec.php b/spec/Authentication/BearerSpec.php
index e3d2d88..b053bed 100644
--- a/spec/Authentication/BearerSpec.php
+++ b/spec/Authentication/BearerSpec.php
@@ -24,13 +24,6 @@ function it_has_a_token()
         $this->getToken()->shouldReturn('token');
     }
 
-    function it_accepts_a_token()
-    {
-        $this->setToken('another_token');
-
-        $this->getToken()->shouldReturn('another_token');
-    }
-
     function it_authenticates_a_request(RequestInterface $request, RequestInterface $newRequest)
     {
         $request->withHeader('Authorization', 'Bearer token')->willReturn($newRequest);
diff --git a/spec/Authentication/ChainSpec.php b/spec/Authentication/ChainSpec.php
index f16938f..aa12747 100644
--- a/spec/Authentication/ChainSpec.php
+++ b/spec/Authentication/ChainSpec.php
@@ -24,36 +24,11 @@ function it_accepts_an_authentication_chain_in_the_constructor(Authentication $a
         $this->getAuthenticationChain()->shouldReturn($chain);
     }
 
-    function it_sets_the_authentication_chain(Authentication $auth1, Authentication $auth2)
+    function it_throws_an_exception_when_non_authentication_is_passed()
     {
-        // This SHOULD be replaced
-        $this->beConstructedWith([$auth1]);
+        $this->beConstructedWith(['authentication']);
 
-        $this->setAuthenticationChain([$auth2]);
-
-        $this->getAuthenticationChain()->shouldReturn([$auth2]);
-    }
-
-    function it_adds_an_authentication_method(Authentication $auth1, Authentication $auth2)
-    {
-        // This SHOULD NOT be replaced
-        $this->beConstructedWith([$auth1]);
-
-        $this->addAuthentication($auth2);
-
-        $this->getAuthenticationChain()->shouldReturn([$auth1, $auth2]);
-    }
-
-    function it_clears_the_authentication_chain(Authentication $auth1, Authentication $auth2)
-    {
-        // This SHOULD be replaced
-        $this->beConstructedWith([$auth1]);
-
-        $this->clearAuthenticationChain();
-
-        $this->addAuthentication($auth2);
-
-        $this->getAuthenticationChain()->shouldReturn([$auth2]);
+        $this->shouldThrow('InvalidArgumentException')->duringInstantiation();
     }
 
     function it_authenticates_a_request(
diff --git a/spec/Authentication/MatchingSpec.php b/spec/Authentication/MatchingSpec.php
index caefda6..33306d7 100644
--- a/spec/Authentication/MatchingSpec.php
+++ b/spec/Authentication/MatchingSpec.php
@@ -29,27 +29,11 @@ function it_has_an_authentication(Authentication $authentication)
         $this->getAuthentication()->shouldReturn($authentication);
     }
 
-    function it_accepts_an_authentication(Authentication $anotherAuthentication)
-    {
-        $this->setAuthentication($anotherAuthentication);
-
-        $this->getAuthentication()->shouldReturn($anotherAuthentication);
-    }
-
     function it_has_a_matcher()
     {
         $this->getMatcher()->shouldReturn($this->matcher);
     }
 
-    function it_accepts_a_matcher()
-    {
-        $matcher = function($request) { return false; };
-
-        $this->setMatcher($matcher);
-
-        $this->getMatcher()->shouldReturn($matcher);
-    }
-
     function it_authenticates_a_request(Authentication $authentication, RequestInterface $request, RequestInterface $newRequest)
     {
         $authentication->authenticate($request)->willReturn($newRequest);
@@ -61,7 +45,7 @@ function it_does_not_authenticate_a_request(Authentication $authentication, Requ
     {
         $matcher = function($request) { return false; };
 
-        $this->setMatcher($matcher);
+        $this->beConstructedWith($authentication, $matcher);
 
         $authentication->authenticate($request)->shouldNotBeCalled();
 
diff --git a/spec/Authentication/WsseSpec.php b/spec/Authentication/WsseSpec.php
index 9d511da..4a68521 100644
--- a/spec/Authentication/WsseSpec.php
+++ b/spec/Authentication/WsseSpec.php
@@ -25,25 +25,11 @@ function it_has_a_username()
         $this->getUsername()->shouldReturn('john.doe');
     }
 
-    function it_accepts_a_username()
-    {
-        $this->setUsername('jane.doe');
-
-        $this->getUsername()->shouldReturn('jane.doe');
-    }
-
     function it_has_a_password()
     {
         $this->getPassword()->shouldReturn('secret');
     }
 
-    function it_accepts_a_password()
-    {
-        $this->setPassword('very_secret');
-
-        $this->getPassword()->shouldReturn('very_secret');
-    }
-
     function it_authenticates_a_request(
         RequestInterface $request,
         RequestInterface $newRequest,
diff --git a/src/Authentication/Bearer.php b/src/Authentication/Bearer.php
index fabcf4b..acd052a 100644
--- a/src/Authentication/Bearer.php
+++ b/src/Authentication/Bearer.php
@@ -35,16 +35,6 @@ public function getToken()
         return $this->token;
     }
 
-    /**
-     * Sets the token.
-     *
-     * @param string $token
-     */
-    public function setToken($token)
-    {
-        $this->token = $token;
-    }
-
     /**
      * {@inheritdoc}
      */
diff --git a/src/Authentication/Chain.php b/src/Authentication/Chain.php
index e5899d1..eeb0745 100644
--- a/src/Authentication/Chain.php
+++ b/src/Authentication/Chain.php
@@ -22,19 +22,15 @@ final class Chain implements Authentication
      */
     public function __construct(array $authenticationChain = [])
     {
-        $this->setAuthenticationChain($authenticationChain);
-    }
+        foreach ($authenticationChain as $authentication) {
+            if (!$authentication instanceof Authentication) {
+                throw new \InvalidArgumentException(
+                    'Members of the authentication chain must be of type Http\Message\Authentication'
+                );
+            }
+        }
 
-    /**
-     * Adds an Authentication method to the chain.
-     *
-     * The order of authentication methods SHOULD NOT matter.
-     *
-     * @param Authentication $authentication
-     */
-    public function addAuthentication(Authentication $authentication)
-    {
-        $this->authenticationChain[] = $authentication;
+        $this->authenticationChain = $authenticationChain;
     }
 
     /**
@@ -47,28 +43,6 @@ public function getAuthenticationChain()
         return $this->authenticationChain;
     }
 
-    /**
-     * Replaces the current authentication chain.
-     *
-     * @param array $authenticationChain
-     */
-    public function setAuthenticationChain(array $authenticationChain)
-    {
-        $this->clearAuthenticationChain();
-
-        foreach ($authenticationChain as $authentication) {
-            $this->addAuthentication($authentication);
-        }
-    }
-
-    /**
-     * Clears the authentication chain.
-     */
-    public function clearAuthenticationChain()
-    {
-        $this->authenticationChain = [];
-    }
-
     /**
      * {@inheritdoc}
      */
diff --git a/src/Authentication/Matching.php b/src/Authentication/Matching.php
index 9502a35..ff9bb9b 100644
--- a/src/Authentication/Matching.php
+++ b/src/Authentication/Matching.php
@@ -48,16 +48,6 @@ public function getAuthentication()
         return $this->authentication;
     }
 
-    /**
-     * Sets the authentication.
-     *
-     * @param Authentication $authentication
-     */
-    public function setAuthentication(Authentication $authentication)
-    {
-        $this->authentication = $authentication;
-    }
-
     /**
      * Returns the matcher.
      *
@@ -68,16 +58,6 @@ public function getMatcher()
         return $this->matcher;
     }
 
-    /**
-     * Sets the matcher.
-     *
-     * @param callable $matcher
-     */
-    public function setMatcher(callable $matcher)
-    {
-        $this->matcher = $matcher;
-    }
-
     /**
      * {@inheritdoc}
      */
diff --git a/src/Authentication/UserPasswordPair.php b/src/Authentication/UserPasswordPair.php
index 14f7cda..77113c2 100644
--- a/src/Authentication/UserPasswordPair.php
+++ b/src/Authentication/UserPasswordPair.php
@@ -29,16 +29,6 @@ public function getUsername()
         return $this->username;
     }
 
-    /**
-     * Sets the username.
-     *
-     * @param string $username
-     */
-    public function setUsername($username)
-    {
-        $this->username = $username;
-    }
-
     /**
      * Returns the password.
      *
@@ -48,14 +38,4 @@ public function getPassword()
     {
         return $this->password;
     }
-
-    /**
-     * Sets the password.
-     *
-     * @param string $password
-     */
-    public function setPassword($password)
-    {
-        $this->password = $password;
-    }
 }