diff --git a/src/main/java/com/amihaiemil/docker/Auth.java b/src/main/java/com/amihaiemil/docker/Auth.java
new file mode 100644
index 00000000..db24150a
--- /dev/null
+++ b/src/main/java/com/amihaiemil/docker/Auth.java
@@ -0,0 +1,44 @@
+/**
+ * Copyright (c) 2018, Mihai Emil Andronache
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1)Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2)Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3)Neither the name of docker-java-api nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.amihaiemil.docker;
+
+/**
+ * Authentication for Docker API.
+ * @author George Aristy (george.aristy@gmail.com)
+ * @version $Id$
+ * @see <a href="https://docs.docker.com/engine/api/v1.35/#section/Authentication">Authentication</a>
+ * @since 0.0.1
+ * @todo #99:30min Implement a new auth named 'Token' that will hold the user's
+ *  identity token from the auth endpoint. Implement some operation that would
+ *  call the /auth endpoint and obtain a token.
+ */
+public interface Auth {
+    /**
+     * This {@link Auth} as a Base-64 encoded string.
+     * @return This auth as a base64-encoded string.
+     */
+    String encoded();
+}
diff --git a/src/main/java/com/amihaiemil/docker/AuthHttpClient.java b/src/main/java/com/amihaiemil/docker/AuthHttpClient.java
new file mode 100644
index 00000000..299c6b56
--- /dev/null
+++ b/src/main/java/com/amihaiemil/docker/AuthHttpClient.java
@@ -0,0 +1,144 @@
+/**
+ * Copyright (c) 2018, Mihai Emil Andronache
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1)Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2)Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3)Neither the name of docker-java-api nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.amihaiemil.docker;
+
+import java.io.IOException;
+import org.apache.http.HttpHost;
+import org.apache.http.HttpRequest;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.ResponseHandler;
+import org.apache.http.client.methods.HttpUriRequest;
+import org.apache.http.conn.ClientConnectionManager;
+import org.apache.http.params.HttpParams;
+import org.apache.http.protocol.HttpContext;
+
+/**
+ * An authenticated HttpClient.
+ * @author George Aristy (george.aristy@gmail.com)
+ * @version $Id$
+ * @since 0.0.1
+ * @todo #99:30min Start decorating our internal HttpClients with this one
+ *  for calls that require authentication headers.
+ */
+final class AuthHttpClient implements HttpClient {
+    /**
+     * The decorated HttpClient.
+     */
+    private final HttpClient origin;
+    /**
+     * The authentication to inject into requests.
+     */
+    private final Auth authentication;
+
+    /**
+     * Ctor.
+     * @param origin The HttpClient to decorate.
+     * @param authentication The authentication to inject into requests.
+     */
+    AuthHttpClient(final HttpClient origin, final Auth authentication) {
+        this.origin = origin;
+        this.authentication = authentication;
+    }
+
+    @Override
+    public HttpParams getParams() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public ClientConnectionManager getConnectionManager() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public HttpResponse execute(final HttpUriRequest request)
+        throws IOException, ClientProtocolException {
+        final String header = "X-Registry-Auth";
+        if (!request.containsHeader(header)) {
+            request.setHeader(header, this.authentication.encoded());
+        }
+        return this.origin.execute(request);
+    }
+
+    @Override
+    public HttpResponse execute(
+        final HttpUriRequest request, final HttpContext context
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public HttpResponse execute(
+        final HttpHost target, final HttpRequest request
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public HttpResponse execute(
+        final HttpHost target, final HttpRequest request,
+        final HttpContext context
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public <T> T execute(
+        final HttpUriRequest request,
+        final ResponseHandler<? extends T> responseHandler
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public <T> T execute(
+        final HttpUriRequest request,
+        final ResponseHandler<? extends T> responseHandler,
+        final HttpContext context
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public <T> T execute(
+        final HttpHost target, final HttpRequest request,
+        final ResponseHandler<? extends T> responseHandler
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+
+    // @checkstyle ParameterNumber (5 lines)
+    @Override
+    public <T> T execute(
+        final HttpHost target, final HttpRequest request,
+        final ResponseHandler<? extends T> responseHandler,
+        final HttpContext context
+    ) throws IOException, ClientProtocolException {
+        throw new UnsupportedOperationException();
+    }
+}
diff --git a/src/main/java/com/amihaiemil/docker/Credentials.java b/src/main/java/com/amihaiemil/docker/Credentials.java
new file mode 100644
index 00000000..37f8cb69
--- /dev/null
+++ b/src/main/java/com/amihaiemil/docker/Credentials.java
@@ -0,0 +1,73 @@
+/**
+ * Copyright (c) 2018, Mihai Emil Andronache
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1)Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2)Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3)Neither the name of docker-java-api nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.amihaiemil.docker;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+import java.util.function.Supplier;
+import javax.json.Json;
+
+/**
+ * An {@link Auth} supporting bare user credentials.
+ * @author George Aristy (george.aristy@gmail.com)
+ * @version $Id$
+ * @see <a href="https://docs.docker.com/engine/api/v1.35/#section/Authentication">Authentication</a>
+ * @since 0.0.1
+ */
+public final class Credentials implements Auth {
+    /**
+     * The base64-encoded JSON structure holding the credentials.
+     */
+    private final Supplier<String> encoded;
+
+    /**
+     * Ctor.
+     * @param user The username.
+     * @param pwd The user's password.
+     * @param email The user's email address.
+     * @param server Domain/IP without a protocol.
+     * @checkstyle ParameterNumber (4 lines)
+     */
+    public Credentials(
+        final String user, final String pwd,
+        final String email, final String server
+    ) {
+        this.encoded = () -> Base64.getEncoder().encodeToString(
+            Json.createObjectBuilder()
+                .add("username", user)
+                .add("password", pwd)
+                .add("email", email)
+                .add("serveraddress", server)
+                .build().toString()
+                .getBytes(StandardCharsets.UTF_8)
+        );
+    }
+  
+    @Override
+    public String encoded() {
+        return this.encoded.get();
+    }
+}
diff --git a/src/main/java/com/amihaiemil/docker/RtImages.java b/src/main/java/com/amihaiemil/docker/RtImages.java
index 7aeefe50..41144dda 100644
--- a/src/main/java/com/amihaiemil/docker/RtImages.java
+++ b/src/main/java/com/amihaiemil/docker/RtImages.java
@@ -93,11 +93,6 @@ public Iterable<Image> iterate() throws IOException {
         }
     }
 
-    // @todo #83:30min Several API calls required an authentication header as
-    //  explained here:
-    //  https://docs.docker.com/engine/api/v1.35/#section/Authentication
-    //  (including Images.create()). Find a way to make a reusable object from
-    //  that action and introduce it here.
     // @checkstyle ParameterNumber (4 lines)
     @Override
     public Images create(
diff --git a/src/test/java/com/amihaiemil/docker/AuthHttpClientTestCase.java b/src/test/java/com/amihaiemil/docker/AuthHttpClientTestCase.java
new file mode 100644
index 00000000..c4fbd2f2
--- /dev/null
+++ b/src/test/java/com/amihaiemil/docker/AuthHttpClientTestCase.java
@@ -0,0 +1,92 @@
+/**
+ * Copyright (c) 2018, Mihai Emil Andronache
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1)Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2)Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3)Neither the name of docker-java-api nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.amihaiemil.docker;
+
+import org.apache.http.Header;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpUriRequest;
+import org.apache.http.message.BasicHeader;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+/**
+ * Unit tests for {@link AuthHttpClient}.
+ * @author George Aristy (george.aristy@gmail.com)
+ * @version $Id$
+ * @since 0.0.1
+ */
+public final class AuthHttpClientTestCase {
+    /**
+     * Mock HttpClient that does nothing.
+     */
+    private static HttpClient noOpClient;
+
+    /**
+     * Setup the mock http client.
+     * @throws Exception If something does wrong.
+     */
+    @BeforeClass
+    public static void setup() throws Exception {
+        noOpClient = Mockito.mock(HttpClient.class);
+        Mockito.when(noOpClient.execute(Mockito.any(HttpUriRequest.class)))
+            .thenReturn(null);
+    }
+
+    /**
+     * Must inject the X-Registry-Auth header if absent and set it to the
+     * auth's value.
+     * @throws Exception If something goes wrong.
+     */
+    @Test
+    public void injectsHeaderIfAbsent() throws Exception {
+        final HttpUriRequest request = new HttpGet();
+        new AuthHttpClient(noOpClient, () -> "123").execute(request);
+        MatcherAssert.assertThat(
+            request.getFirstHeader("X-Registry-Auth").getValue(),
+            Matchers.is("123")
+        );
+    }
+
+    /**
+     * Leaves the request's header instact if it exists.
+     * @throws Exception If something goes wrong.
+     */
+    @Test
+    public void leavesExistingHeaderAlone() throws Exception {
+        final Header auth = new BasicHeader("X-Registry-Auth", "12356");
+        final HttpUriRequest request = new HttpGet();
+        request.setHeader(auth);
+        new AuthHttpClient(noOpClient, () -> "abc").execute(request);
+        MatcherAssert.assertThat(
+            request.getFirstHeader("X-Registry-Auth"),
+            Matchers.is(auth)
+        );
+    }
+}
diff --git a/src/test/java/com/amihaiemil/docker/CredentialsTestCase.java b/src/test/java/com/amihaiemil/docker/CredentialsTestCase.java
new file mode 100644
index 00000000..ee919a8a
--- /dev/null
+++ b/src/test/java/com/amihaiemil/docker/CredentialsTestCase.java
@@ -0,0 +1,64 @@
+/**
+ * Copyright (c) 2018, Mihai Emil Andronache
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 1)Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2)Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3)Neither the name of docker-java-api nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.amihaiemil.docker;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+import javax.json.Json;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.Test;
+
+/**
+ * Unit tests for {@link Credentials}.
+ * @author George Aristy (george.aristy@gmail.com)
+ * @version $Id$
+ * @since 0.0.1
+ */
+public final class CredentialsTestCase {
+    /**
+     * Correctly encodes to base64 all attributes as a JSON object.
+     */
+    @Test
+    public void correctEncoding() {
+        MatcherAssert.assertThat(
+            new Credentials(
+                "user", "pass", "john@doe.com", "server"
+            ).encoded(),
+            Matchers.is(
+                Base64.getEncoder().encodeToString(
+                    Json.createObjectBuilder()
+                        .add("username", "user")
+                        .add("password", "pass")
+                        .add("email", "john@doe.com")
+                        .add("serveraddress", "server")
+                        .build().toString()
+                        .getBytes(StandardCharsets.UTF_8)
+                )
+            )
+        );
+    }
+}