diff --git a/client/src/room/event.rs b/client/src/room/event.rs
index 28e0cc6..aee5845 100644
--- a/client/src/room/event.rs
+++ b/client/src/room/event.rs
@@ -1,3 +1,5 @@
+//! This module defines events affecting the room module and their handling.
+
 use solstice_proto::server::{
   RoomJoinResponse, RoomListResponse, RoomMessageResponse,
 };
@@ -11,6 +13,7 @@ use crate::handlers::{
 };
 use crate::message_handler::MessageHandler;
 
+/// An event affecting the chat room module.
 #[derive(Debug, PartialEq, Eq)]
 pub enum RoomEvent {
   JoinRequest(String),
@@ -21,7 +24,11 @@ pub enum RoomEvent {
   MessageResponse(RoomMessageResponse),
 }
 
+/// An interface for room event handlers.
+///
+/// Allows mocking of handlers in tests.
 pub trait HandleRoomEvent {
+  /// Handles the given `event` against the given global `context`.
   fn handle(
     &mut self,
     context: &mut Context,
@@ -29,6 +36,7 @@ pub trait HandleRoomEvent {
   ) -> anyhow::Result<()>;
 }
 
+/// The real, default implementation of `HandleRoomEvent`.
 #[derive(Default)]
 pub struct RoomEventHandler;
 
diff --git a/client/src/room/map.rs b/client/src/room/map.rs
index 21d3fea..cadb82e 100644
--- a/client/src/room/map.rs
+++ b/client/src/room/map.rs
@@ -1,3 +1,6 @@
+//! This module defines abstractions for handling the global set of rooms and
+//! their state.
+
 use std::collections::HashMap;
 use std::mem;
 
diff --git a/client/src/room/state.rs b/client/src/room/state.rs
index a0599f9..91be6e8 100644
--- a/client/src/room/state.rs
+++ b/client/src/room/state.rs
@@ -1,3 +1,6 @@
+//! This module defines the data structures used for room state storage and
+//! serialization.
+
 use std::collections::HashSet;
 use std::time::SystemTime;