diff --git a/src/frame/session.rs b/src/frame/session.rs
index 7dcbe58da3..0a9cfc02b0 100644
--- a/src/frame/session.rs
+++ b/src/frame/session.rs
@@ -16,7 +16,10 @@
 // Copyright 2019-2020 Parity Technologies (UK) Ltd.
 
 //! Session support
-use crate::frame::system::System;
+use crate::frame::system::{
+    System,
+    SystemEventsDecoder as _,
+};
 use codec::Encode;
 use frame_support::Parameter;
 use std::{
@@ -26,14 +29,14 @@ use std::{
 use substrate_subxt_proc_macro::Store;
 
 /// The trait needed for this module.
+#[module]
 pub trait Session: System {
     /// The validator account identifier type for the runtime.
-    type ValidatorId: Parameter + Debug + Ord + Default;
-    /// The validator account identifier type for the runtime.
-    type SessionIndex: Parameter + Debug + Ord + Default;
-}
+    type ValidatorId: Parameter + Debug + Ord + Default + Send + Sync + 'static;
 
-const MODULE: &str = "Session";
+    /// The validator account identifier type for the runtime.
+    type SessionIndex: Parameter + Debug + Ord + Default + Send + Sync + 'static;
+}
 
 /// The current set of validators.
 #[derive(Encode, Store)]
diff --git a/src/frame/staking.rs b/src/frame/staking.rs
index 80ec46db18..40b247ac63 100644
--- a/src/frame/staking.rs
+++ b/src/frame/staking.rs
@@ -16,7 +16,10 @@
 
 //! Implements support for the frame_staking module.
 
-use super::system::{System, SystemEventsDecoder as _};
+use super::system::{
+    System,
+    SystemEventsDecoder as _,
+};
 use codec::{
     Decode,
     Encode,
@@ -111,6 +114,7 @@ impl Default for ValidatorPrefs {
 /// The subset of the `frame::Trait` that a client must implement.
 #[module]
 pub trait Staking: System {}
+impl<T: System> Staking for T {}
 
 /// Just a Balance/BlockNumber tuple to encode when a chunk of funds will be unlocked.
 #[derive(PartialEq, Eq, Clone, Encode, Decode)]
diff --git a/src/runtimes.rs b/src/runtimes.rs
index 3ced7ce0b5..10b9bc6f1d 100644
--- a/src/runtimes.rs
+++ b/src/runtimes.rs
@@ -31,6 +31,7 @@ use crate::frame::{
         Balances,
     },
     contracts::Contracts,
+    session::Session,
     system::System,
 };
 
@@ -82,6 +83,11 @@ impl System for KusamaRuntime {
     type AccountData = AccountData<<Self as Balances>::Balance>;
 }
 
+impl Session for KusamaRuntime {
+    type SessionIndex = u32;
+    type ValidatorId = <Self as System>::AccountId;
+}
+
 impl Balances for KusamaRuntime {
     type Balance = u128;
 }