diff --git a/NibasaViewer/settings.py b/NibasaViewer/settings.py
index 2c58bb8..38b732d 100644
--- a/NibasaViewer/settings.py
+++ b/NibasaViewer/settings.py
@@ -104,6 +104,10 @@ AUTH_PASSWORD_VALIDATORS = [
     },
 ]
 
+# Authentication.
+LOGIN_REDIRECT_URL  = '/gallery/'
+LOGOUT_REDIRECT_URL = 'login'
+LOGIN_URL           = 'login'
 
 # Internationalization
 # https://docs.djangoproject.com/en/4.2/topics/i18n/
diff --git a/NibasaViewer/urls.py b/NibasaViewer/urls.py
index 170fee0..273adc5 100644
--- a/NibasaViewer/urls.py
+++ b/NibasaViewer/urls.py
@@ -21,6 +21,9 @@ from django.conf.urls.static import static
 from django.urls             import (path,
                                      include)
 
+from django.contrib.auth import views
+
+# Project imports.
 from viewer.views import index
 
 ###########################################################################################
@@ -31,8 +34,13 @@ urlpatterns = [
     # Index.
     path('', index, name = 'home'),
 
+    # Auth views.
+    path("login/", views.LoginView.as_view(), name = 'login'),
+    path("logout/", views.LogoutView.as_view(), name = 'logout'),
+
     # Add invoices app urls.
     path('gallery/', include('viewer.urls')),
+
 ] + static(settings.STATIC_URL, document_root = settings.STATIC_ROOT)\
   + static('imgs/', document_root = settings.GALLERY_ROOT)\
   + static('thumbs/', document_root = settings.THUMBNAILS_ROOT)
diff --git a/README.md b/README.md
index 2f5a4f3..29e206a 100644
--- a/README.md
+++ b/README.md
@@ -4,4 +4,8 @@ A basic pure HTML+CSS gallery viewer in the vein of [PiGallery 2](https://bpatri
 
 ## User authentication.
 
-Currently there is no authentication at all because I don't need it. This is meant to be installed in a server with HTTP basic auth enabled if needed.
+To login a user should be manually created by running the following commands in the Django shell, substituting the user's name, email and password as needed:
+
+    from django.contrib.auth.models import User
+    user = User.objects.create_user('<USERNAME>', '<EMAIL>', '<PASSWORD>')
+    user.save()
diff --git a/viewer/static/css/styles.css b/viewer/static/css/styles.css
index a29f24a..afbc60c 100644
--- a/viewer/static/css/styles.css
+++ b/viewer/static/css/styles.css
@@ -44,6 +44,10 @@ body {
     width: 100%;
 }
 
+.pd {
+    padding: 10%;
+}
+
 /****************************************************************************
  * Content.                                                                 *
  ****************************************************************************/
@@ -83,7 +87,7 @@ body {
     margin-left: 2em;
 }
 
-.search-btn {
+.clear-btn {
     border: none;
     background-color: #00000000;
 }
@@ -92,6 +96,10 @@ body {
     height: 2.5em;
 }
 
+.float-right {
+    float: right;
+}
+
 /****************************************************************************
  * Grid.                                                                    *
  ****************************************************************************/
diff --git a/viewer/static/imgs/boot.png b/viewer/static/imgs/boot.png
new file mode 100755
index 0000000..d32bd98
Binary files /dev/null and b/viewer/static/imgs/boot.png differ
diff --git a/viewer/templates/gallery_view.html b/viewer/templates/gallery_view.html
index 649714e..a7f1dbe 100644
--- a/viewer/templates/gallery_view.html
+++ b/viewer/templates/gallery_view.html
@@ -43,11 +43,21 @@
                 <!-- Page links. -->
                 {% if num_pages > 1 %}
                 <td>
-                    <div class="mauto">
+                    <div class="mauto mr-2">
                         {% for page in pages %}<a href="./?page={{page}}{%if search %}&{{search}}{% endif %}">{{page}}</a>{% if not forloop.last %}<span> </span>{% endif %}{% endfor %}
                     </div>
                 </td>
                 {% endif %}
+
+                <!-- Logout button. -->
+                <td>
+                    <form method="post" action="{% url 'logout' %}">
+                        {% csrf_token %}
+                        <button type="submit" class="clear-btn">
+                            <img src="{% static 'imgs/boot.png' %}" class="small-nav-icon">
+                        </button>
+                    </form>
+                </td>
             </tr>
         </table>
 
@@ -70,7 +80,7 @@
 
                     <!-- Search submit. -->
                     <td>
-                        <button type="submit" class="search-btn">
+                        <button type="submit" class="clear-btn">
                             <img src="{% static 'imgs/find.png' %}" class="small-nav-icon">
                         </button>
                     </td>
diff --git a/viewer/templates/registration/login.html b/viewer/templates/registration/login.html
new file mode 100644
index 0000000..0232546
--- /dev/null
+++ b/viewer/templates/registration/login.html
@@ -0,0 +1,42 @@
+{% load static %}
+<!DOCTYPE html>
+<html>
+    <head>
+        <meta name="viewport" content="width=device-width, height=device-height" />
+        <title>
+            NibasaViewer login
+        </title>
+        <link href="{% static 'css/styles.css' %}" rel="stylesheet">
+    </head>
+
+    <body class="background">
+        <div class="fc mauto pd">
+            <form method="post" action="{% url 'login' %}" class="fc">
+                {% csrf_token %}
+                <table>
+                    <tr>
+                        <td>
+                            {{ form.username.label_tag }}
+                        </td>
+                        <td>
+                            {{ form.username }}
+                        </td>
+                    </tr>
+
+                    <tr>
+                        <td>
+                            {{ form.password.label_tag }}
+                        </td>
+                        <td>
+                            {{ form.password }}
+                        </td>
+                    </tr>
+                </table>
+
+                <input type="submit" value="login" class="float-right">
+                <input type="hidden" name="next" value="{{ next }}">
+            </form>
+        </div>
+    </body>
+</html>
+
diff --git a/viewer/views.py b/viewer/views.py
index 32e72b5..2f4e19b 100644
--- a/viewer/views.py
+++ b/viewer/views.py
@@ -6,11 +6,15 @@ from math    import ceil
 import filetype
 
 # Django imports.
-from django.http       import HttpResponseNotFound
-from django.conf       import settings
-from django.utils.http import urlencode
-from django.shortcuts  import (render,
-                               redirect)
+from django.http                    import HttpResponseNotFound
+from django.conf                    import settings
+from django.utils.http              import urlencode
+from django.contrib.auth.decorators import login_required
+from django.contrib.auth            import (authenticate,
+                                            login,
+                                            logout)
+from django.shortcuts               import (render,
+                                            redirect)
 
 # Project imports.
 from .utils import make_thumbnail
@@ -24,12 +28,9 @@ ROWS_PER_PAGE   = 4
 IMAGES_PER_PAGE = CELLS_PER_ROW * ROWS_PER_PAGE
 
 ###########################################################################################
-# View functions.                                                                         #
+# Helper functions.                                                                       #
 ###########################################################################################
 
-def index(request):
-    return redirect('gallery_view_root')
-
 def do_recursive_search(start_path, query):
     """
     Gets all images and sub-directories inside the start_path whose name matches the given query,
@@ -56,6 +57,11 @@ def do_recursive_search(start_path, query):
 # View functions.                                                                         #
 ###########################################################################################
 
+@login_required
+def index(request):
+    return redirect('gallery_view_root')
+
+@login_required
 def gallery_view(request, path = None):
     """
     Shows a list of subdirectories and image files inside the given path.