diff --git a/hosts/p14s/configuration.nix b/hosts/p14s/configuration.nix
index e729bfb..4264fbe 100644
--- a/hosts/p14s/configuration.nix
+++ b/hosts/p14s/configuration.nix
@@ -8,7 +8,7 @@
   imports =
     [ # Include the results of the hardware scan.
       ./hardware-configuration.nix
-      ../../modules/xfce.nix
+      ../../modules/system/xfce.nix
     ];
 
   # Bootloader.
diff --git a/modules/README.md b/modules/README.md
new file mode 100644
index 0000000..ce6965f
--- /dev/null
+++ b/modules/README.md
@@ -0,0 +1,11 @@
+# Modules
+
+Organized Nix modules.
+```
+.
+|
++-- system       - Modules to be included in configuration.nix
++-- home-manager - Modules for home-manager
++-- dotfiles     - Static configuration files (e.g. for ~/.config)
+```
+
diff --git a/modules/xfce.nix b/modules/system/xfce.nix
similarity index 100%
rename from modules/xfce.nix
rename to modules/system/xfce.nix