diff --git a/src/client/mod.rs b/src/client/mod.rs
index 025293be..937c0dc9 100644
--- a/src/client/mod.rs
+++ b/src/client/mod.rs
@@ -1,13 +1,4 @@
-#[cfg(feature = "rtu")]
-pub mod rtu;
-
-#[cfg(feature = "sync")]
-pub mod sync;
-
-#[cfg(feature = "tcp")]
-pub mod tcp;
-
-use crate::{frame::*, slave::*};
+//! Modbus clients
 
 use std::{
     fmt::Debug,
@@ -16,24 +7,44 @@ use std::{
 
 use async_trait::async_trait;
 
-/// A transport independent asynchronous client trait.
+use crate::{frame::*, slave::*};
+
+#[cfg(feature = "sync")]
+pub mod sync;
+
+#[cfg(feature = "rtu")]
+pub mod rtu;
+
+#[cfg(feature = "tcp")]
+pub mod tcp;
+
+/// Transport independent asynchronous client trait
 #[async_trait]
 pub trait Client: SlaveContext + Send + Debug {
+    /// Invoke a Modbus function
     async fn call(&mut self, request: Request) -> Result<Response, Error>;
 }
 
-/// An asynchronous Modbus reader.
+/// Asynchronous Modbus reader
 #[async_trait]
 pub trait Reader: Client {
+    /// Read multiple coils (0x01)
     async fn read_coils(&mut self, _: Address, _: Quantity) -> Result<Vec<Coil>, Error>;
 
+    /// Read multiple discrete inputs (0x02)
     async fn read_discrete_inputs(&mut self, _: Address, _: Quantity) -> Result<Vec<Coil>, Error>;
 
-    async fn read_input_registers(&mut self, _: Address, _: Quantity) -> Result<Vec<Word>, Error>;
-
+    /// Read multiple holding registers (0x03)
     async fn read_holding_registers(&mut self, _: Address, _: Quantity)
         -> Result<Vec<Word>, Error>;
 
+    /// Read multiple input registers (0x04)
+    async fn read_input_registers(&mut self, _: Address, _: Quantity) -> Result<Vec<Word>, Error>;
+
+    /// Read and write multiple holding registers (0x17)
+    ///
+    /// The write operation is performed before the read unlike
+    /// the name of the operation might suggest!
     async fn read_write_multiple_registers(
         &mut self,
         _: Address,
@@ -43,25 +54,30 @@ pub trait Reader: Client {
     ) -> Result<Vec<Word>, Error>;
 }
 
-/// An asynchronous Modbus writer.
+/// Asynchronous Modbus writer
 #[async_trait]
 pub trait Writer: Client {
+    /// Write a single coil (0x05)
     async fn write_single_coil(&mut self, _: Address, _: Coil) -> Result<(), Error>;
 
-    async fn write_multiple_coils(&mut self, _: Address, _: &[Coil]) -> Result<(), Error>;
-
+    /// Write a single holding register (0x06)
     async fn write_single_register(&mut self, _: Address, _: Word) -> Result<(), Error>;
 
+    /// Write multiple coils (0x0F)
+    async fn write_multiple_coils(&mut self, _: Address, _: &[Coil]) -> Result<(), Error>;
+
+    /// Write multiple holding registers (0x10)
     async fn write_multiple_registers(&mut self, _: Address, _: &[Word]) -> Result<(), Error>;
 }
 
-/// An asynchronous Modbus client context.
+/// Asynchronous Modbus client context
 #[derive(Debug)]
 pub struct Context {
     client: Box<dyn Client>,
 }
 
 impl Context {
+    /// Disconnect the client
     pub async fn disconnect(&mut self) -> Result<(), Error> {
         // Disconnecting is expected to fail!
         let res = self.client.call(Request::Disconnect).await;
diff --git a/src/client/rtu.rs b/src/client/rtu.rs
index 3b50a4a6..ea65e8e1 100644
--- a/src/client/rtu.rs
+++ b/src/client/rtu.rs
@@ -1,4 +1,4 @@
-//! Connecting a Modbus RTU context
+//! RTU client connections
 
 use super::*;
 
diff --git a/src/client/sync/mod.rs b/src/client/sync/mod.rs
index cc2d9b89..c08f3c8a 100644
--- a/src/client/sync/mod.rs
+++ b/src/client/sync/mod.rs
@@ -1,8 +1,13 @@
-//! Synchronous Modbus context access
+//! Synchronous Modbus client
 
+// TODO: Add missing documentation
+#![allow(missing_docs)]
+
+/// RTU client connections
 #[cfg(feature = "rtu")]
 pub mod rtu;
 
+/// TCP client connections
 #[cfg(feature = "tcp")]
 pub mod tcp;
 
diff --git a/src/client/sync/rtu.rs b/src/client/sync/rtu.rs
index f61fb53f..7a94eeb2 100644
--- a/src/client/sync/rtu.rs
+++ b/src/client/sync/rtu.rs
@@ -1,10 +1,10 @@
 use super::{Context, Result};
 
+use tokio_serial::{SerialPortBuilder, SerialStream};
+
 use crate::client::rtu::connect_slave as async_connect_slave;
 use crate::slave::Slave;
 
-use tokio_serial::{SerialPortBuilder, SerialStream};
-
 /// Connect to no particular Modbus slave device for sending
 /// broadcast messages.
 pub fn connect(builder: &SerialPortBuilder) -> Result<Context> {
diff --git a/src/client/sync/tcp.rs b/src/client/sync/tcp.rs
index f562bed1..19bab618 100644
--- a/src/client/sync/tcp.rs
+++ b/src/client/sync/tcp.rs
@@ -1,9 +1,12 @@
-use super::{Context, Result};
+//! TCP client connections
+
+use std::net::SocketAddr;
 
 use crate::client::tcp::connect_slave as async_connect_slave;
 use crate::slave::Slave;
 
-use std::net::SocketAddr;
+use super::{Context, Result};
+
 /// Establish a direct connection to a Modbus TCP coupler.
 pub fn connect(socket_addr: SocketAddr) -> Result<Context> {
     connect_slave(socket_addr, Slave::tcp_device())
diff --git a/src/client/tcp.rs b/src/client/tcp.rs
index 75b4190f..8ef1e671 100644
--- a/src/client/tcp.rs
+++ b/src/client/tcp.rs
@@ -1,4 +1,4 @@
-//! Connecting a Modbus TCP context
+//! TCP client connections
 
 use super::*;
 
diff --git a/src/lib.rs b/src/lib.rs
index 3232e530..c2001ad1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -144,8 +144,7 @@
 #![deny(rust_2018_idioms)]
 #![deny(rust_2021_compatibility)]
 #![deny(missing_debug_implementations)]
-// TODO: Add missing documentation
-//#![deny(missing_docs)]
+#![deny(missing_docs)]
 #![deny(rustdoc::broken_intra_doc_links)]
 #![deny(clippy::all)]
 #![deny(clippy::explicit_deref_methods)]
@@ -162,6 +161,7 @@
 pub mod prelude;
 
 pub mod client;
+
 pub mod slave;
 
 #[cfg(feature = "server")]
diff --git a/src/prelude.rs b/src/prelude.rs
index a883145c..91ea8004 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -1,16 +1,23 @@
+//! Common types
+
 ///////////////////////////////////////////////////////////////////
 /// Modules
 ///////////////////////////////////////////////////////////////////
 pub use crate::client;
 
-#[cfg(feature = "server")]
-pub use crate::server;
+#[allow(missing_docs)]
+#[cfg(feature = "sync")]
+pub mod sync {
+    pub use crate::client::sync::*;
+}
 
+#[allow(missing_docs)]
 #[cfg(feature = "rtu")]
 pub mod rtu {
     pub use crate::client::rtu::*;
 }
 
+#[allow(missing_docs)]
 #[cfg(feature = "tcp")]
 pub mod tcp {
     pub use crate::client::tcp::*;
@@ -19,10 +26,8 @@ pub mod tcp {
     pub use crate::server::*;
 }
 
-#[cfg(feature = "sync")]
-pub mod sync {
-    pub use crate::client::sync::*;
-}
+#[cfg(feature = "server")]
+pub use crate::server;
 
 ///////////////////////////////////////////////////////////////////
 /// Structs
diff --git a/src/server/mod.rs b/src/server/mod.rs
index 07bceda1..d71d5380 100644
--- a/src/server/mod.rs
+++ b/src/server/mod.rs
@@ -1,5 +1,11 @@
+//! Modbus server skeletons
+
+// TODO: Add missing documentation
+#![allow(missing_docs)]
+
 #[cfg(feature = "rtu")]
 pub mod rtu;
+
 #[cfg(feature = "tcp-server-unstable")]
 pub mod tcp;
 
diff --git a/src/server/rtu.rs b/src/server/rtu.rs
index 6041b8d4..a3bb5337 100644
--- a/src/server/rtu.rs
+++ b/src/server/rtu.rs
@@ -1,6 +1,4 @@
-/*!
- * Modbus RTU server functionality
- */
+//! Modbus RTU server skeleton
 
 use crate::{
     codec,
diff --git a/src/server/tcp.rs b/src/server/tcp.rs
index 34260656..1996ae76 100644
--- a/src/server/tcp.rs
+++ b/src/server/tcp.rs
@@ -1,3 +1,5 @@
+//! Modbus TCP server skeleton
+
 use crate::{
     codec,
     frame::*,
diff --git a/src/slave.rs b/src/slave.rs
index 21f3d52a..994fec05 100644
--- a/src/slave.rs
+++ b/src/slave.rs
@@ -1,5 +1,8 @@
+//! Modbus devices
+
 use std::{fmt, num::ParseIntError, str::FromStr};
 
+/// Slave identifier
 pub type SlaveId = u8;
 
 /// A single byte for addressing Modbus slave devices.
@@ -39,14 +42,17 @@ impl Slave {
         Slave(255)
     }
 
+    /// Check if the [`SlaveId`] is used for broadcasting
     pub fn is_broadcast(self) -> bool {
         self == Self::broadcast()
     }
 
+    /// Check if the [`SlaveId`] addresses a single device
     pub fn is_single_device(self) -> bool {
         self >= Self::min_device() && self <= Self::max_device()
     }
 
+    /// Check if the [`SlaveId`] is reserved
     pub fn is_reserved(self) -> bool {
         self > Self::max_device()
     }