diff --git a/Cargo.lock b/Cargo.lock
index 7f8f7bd555f2d..3537571009c85 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3459,6 +3459,7 @@ dependencies = [
  "srml-session 2.0.0",
  "srml-support 2.0.0",
  "srml-system 2.0.0",
+ "srml-timestamp 2.0.0",
  "substrate-finality-grandpa-primitives 2.0.0",
  "substrate-primitives 2.0.0",
 ]
diff --git a/core/sr-primitives/src/testing.rs b/core/sr-primitives/src/testing.rs
index 18c65d011e657..4b7b2ac83300e 100644
--- a/core/sr-primitives/src/testing.rs
+++ b/core/sr-primitives/src/testing.rs
@@ -22,7 +22,6 @@ use crate::codec::{Codec, Encode, Decode};
 use crate::traits::{self, Checkable, Applyable, BlakeTwo256, Convert};
 use crate::generic::DigestItem as GenDigestItem;
 pub use substrate_primitives::H256;
-use substrate_primitives::U256;
 use substrate_primitives::sr25519::{Public as AuthorityId, Signature as AuthoritySignature};
 
 /// Authority Id
@@ -31,7 +30,7 @@ use substrate_primitives::sr25519::{Public as AuthorityId, Signature as Authorit
 pub struct UintAuthorityId(pub u64);
 impl Into<AuthorityId> for UintAuthorityId {
 	fn into(self) -> AuthorityId {
-		let bytes: [u8; 32] = U256::from(self.0).into();
+		let bytes: [u8; 32] = H256::from_low_u64_be(self.0).into();
 		AuthorityId(bytes)
 	}
 }
diff --git a/node/cli/src/chain_spec.rs b/node/cli/src/chain_spec.rs
index 336636fef884b..ae4812126907a 100644
--- a/node/cli/src/chain_spec.rs
+++ b/node/cli/src/chain_spec.rs
@@ -81,7 +81,7 @@ fn staging_testnet_config_genesis() -> GenesisConfig {
 	GenesisConfig {
 		consensus: Some(ConsensusConfig {
 			code: include_bytes!("../../runtime/wasm/target/wasm32-unknown-unknown/release/node_runtime.compact.wasm").to_vec(),    // FIXME change once we have #1252
-			authorities: initial_authorities.iter().map(|x| x.2.clone()).collect(),
+			authorities: initial_authorities.iter().map(|x| (x.1.clone(), x.2.clone())).collect(),
 		}),
 		system: None,
 		balances: Some(BalancesConfig {
@@ -104,7 +104,7 @@ fn staging_testnet_config_genesis() -> GenesisConfig {
 		session: Some(SessionConfig {
 			validators: initial_authorities.iter().map(|x| x.1.clone()).collect(),
 			session_length: 5 * MINUTES,
-			keys: initial_authorities.iter().map(|x| (x.1.clone(), x.2.clone())).collect::<Vec<_>>(),
+			keys: initial_authorities.iter().map(|x| (x.1.clone(), (x.1.clone(), x.2.clone()))).collect::<Vec<_>>(),
 		}),
 		staking: Some(StakingConfig {
 			current_era: 0,
@@ -270,7 +270,7 @@ pub fn testnet_genesis(
 	GenesisConfig {
 		consensus: Some(ConsensusConfig {
 			code: include_bytes!("../../runtime/wasm/target/wasm32-unknown-unknown/release/node_runtime.compact.wasm").to_vec(),
-			authorities: initial_authorities.iter().map(|x| x.2.clone()).collect(),
+			authorities: initial_authorities.iter().map(|x| (x.1.clone(), x.2.clone())).collect(),
 		}),
 		system: None,
 		indices: Some(IndicesConfig {
@@ -288,7 +288,7 @@ pub fn testnet_genesis(
 		session: Some(SessionConfig {
 			validators: initial_authorities.iter().map(|x| x.1.clone()).collect(),
 			session_length: 10,
-			keys: initial_authorities.iter().map(|x| (x.1.clone(), x.2.clone())).collect::<Vec<_>>(),
+			keys: initial_authorities.iter().map(|x| (x.1.clone(), (x.1.clone(), x.2.clone()))).collect::<Vec<_>>(),
 		}),
 		staking: Some(StakingConfig {
 			current_era: 0,
diff --git a/node/runtime/src/lib.rs b/node/runtime/src/lib.rs
index d243357fc2e30..93a1ed80df4b9 100644
--- a/node/runtime/src/lib.rs
+++ b/node/runtime/src/lib.rs
@@ -86,6 +86,8 @@ impl Convert<u128, u128> for CurrencyToVoteHandler {
 	fn convert(x: u128) -> u128 { x * Self::factor() }
 }
 
+pub type SessionKey = (AccountId, AuthorityId);
+
 impl system::Trait for Runtime {
 	type Origin = Origin;
 	type Index = Index;
@@ -123,13 +125,20 @@ impl balances::Trait for Runtime {
 
 impl consensus::Trait for Runtime {
 	type Log = Log;
-	type SessionKey = AuthorityId;
+	type SessionKey = SessionKey;
 
 	// The Aura module handles offline-reports internally
 	// rather than using an explicit report system.
 	type InherentOfflineReport = ();
 }
 
+pub struct ConvertSessionKeyToAuthorityId;
+impl Convert<SessionKey, AuthorityId> for ConvertSessionKeyToAuthorityId {
+  fn convert(session_key: SessionKey) -> AuthorityId {
+    session_key.1
+  }
+}
+
 impl timestamp::Trait for Runtime {
 	type Moment = u64;
 	type OnTimestampSet = Aura;
@@ -198,7 +207,8 @@ impl sudo::Trait for Runtime {
 }
 
 impl grandpa::Trait for Runtime {
-	type SessionKey = AuthorityId;
+	type LocalSessionKey = AuthorityId;
+	type ConvertLocalSessionKey = ConvertSessionKeyToAuthorityId;
 	type Log = Log;
 	type Event = Event;
 }
@@ -208,7 +218,7 @@ impl finality_tracker::Trait for Runtime {
 }
 
 construct_runtime!(
-	pub enum Runtime with Log(InternalLog: DigestItem<Hash, AuthorityId, AuthoritySignature>) where
+	pub enum Runtime with Log(InternalLog: DigestItem<Hash, SessionKey, AuthoritySignature>) where
 		Block = Block,
 		NodeBlock = node_primitives::Block,
 		UncheckedExtrinsic = UncheckedExtrinsic
diff --git a/srml/grandpa/Cargo.toml b/srml/grandpa/Cargo.toml
index 7855019af8a4d..0fd7ecf53911e 100644
--- a/srml/grandpa/Cargo.toml
+++ b/srml/grandpa/Cargo.toml
@@ -19,6 +19,7 @@ finality-tracker = { package = "srml-finality-tracker", path = "../finality-trac
 
 [dev-dependencies]
 runtime_io = { package = "sr-io", path = "../../core/sr-io" }
+timestamp = { package = "srml-timestamp", path = "../timestamp", default-features = false }
 
 [features]
 default = ["std"]
diff --git a/srml/grandpa/src/lib.rs b/srml/grandpa/src/lib.rs
index 5425ace8bb89e..0ea511bc4c2c1 100644
--- a/srml/grandpa/src/lib.rs
+++ b/srml/grandpa/src/lib.rs
@@ -43,7 +43,7 @@ use srml_support::storage::unhashed::StorageVec;
 use primitives::traits::CurrentHeight;
 use substrate_primitives::ed25519;
 use system::ensure_signed;
-use primitives::traits::MaybeSerializeDebug;
+use primitives::traits::{Convert, MaybeSerializeDebug};
 use ed25519::Public as AuthorityId;
 
 mod mock;
@@ -58,7 +58,7 @@ impl<S: codec::Codec + Default> StorageVec for AuthorityStorageVec<S> {
 /// The log type of this crate, projected from module trait type.
 pub type Log<T> = RawLog<
 	<T as system::Trait>::BlockNumber,
-	<T as Trait>::SessionKey,
+	<T as Trait>::LocalSessionKey,
 >;
 
 /// Logs which can be scanned by GRANDPA for authorities change events.
@@ -72,19 +72,19 @@ pub trait GrandpaChangeSignal<N> {
 /// A logs in this module.
 #[cfg_attr(feature = "std", derive(Serialize, Debug))]
 #[derive(Encode, Decode, PartialEq, Eq, Clone)]
-pub enum RawLog<N, SessionKey> {
+pub enum RawLog<N, LocalSessionKey> {
 	/// Authorities set change has been signaled. Contains the new set of authorities
 	/// and the delay in blocks _to finalize_ before applying.
-	AuthoritiesChangeSignal(N, Vec<(SessionKey, u64)>),
+	AuthoritiesChangeSignal(N, Vec<(LocalSessionKey, u64)>),
 	/// A forced authorities set change. Contains in this order: the median last
 	/// finalized block when the change was signaled, the delay in blocks _to import_
 	/// before applying and the new set of authorities.
-	ForcedAuthoritiesChangeSignal(N, N, Vec<(SessionKey, u64)>),
+	ForcedAuthoritiesChangeSignal(N, N, Vec<(LocalSessionKey, u64)>),
 }
 
-impl<N: Clone, SessionKey> RawLog<N, SessionKey> {
+impl<N: Clone, LocalSessionKey> RawLog<N, LocalSessionKey> {
 	/// Try to cast the log entry as a contained signal.
-	pub fn as_signal(&self) -> Option<(N, &[(SessionKey, u64)])> {
+	pub fn as_signal(&self) -> Option<(N, &[(LocalSessionKey, u64)])> {
 		match *self {
 			RawLog::AuthoritiesChangeSignal(ref delay, ref signal) => Some((delay.clone(), signal)),
 			RawLog::ForcedAuthoritiesChangeSignal(_, _, _) => None,
@@ -92,7 +92,7 @@ impl<N: Clone, SessionKey> RawLog<N, SessionKey> {
 	}
 
 	/// Try to cast the log entry as a contained forced signal.
-	pub fn as_forced_signal(&self) -> Option<(N, N, &[(SessionKey, u64)])> {
+	pub fn as_forced_signal(&self) -> Option<(N, N, &[(LocalSessionKey, u64)])> {
 		match *self {
 			RawLog::ForcedAuthoritiesChangeSignal(ref median, ref delay, ref signal) => Some((median.clone(), delay.clone(), signal)),
 			RawLog::AuthoritiesChangeSignal(_, _) => None,
@@ -100,8 +100,8 @@ impl<N: Clone, SessionKey> RawLog<N, SessionKey> {
 	}
 }
 
-impl<N, SessionKey> GrandpaChangeSignal<N> for RawLog<N, SessionKey>
-	where N: Clone, SessionKey: Clone + Into<AuthorityId>,
+impl<N, LocalSessionKey> GrandpaChangeSignal<N> for RawLog<N, LocalSessionKey>
+	where N: Clone, LocalSessionKey: Clone + Into<AuthorityId>,
 {
 	fn as_signal(&self) -> Option<ScheduledChange<N>> {
 		RawLog::as_signal(self).map(|(delay, next_authorities)| ScheduledChange {
@@ -124,12 +124,15 @@ impl<N, SessionKey> GrandpaChangeSignal<N> for RawLog<N, SessionKey>
 	}
 }
 
-pub trait Trait: system::Trait {
+pub trait Trait: session::Trait + system::Trait {
 	/// Type for all log entries of this module.
 	type Log: From<Log<Self>> + Into<system::DigestItemOf<Self>>;
 
 	/// The session key type used by authorities.
-	type SessionKey: Parameter + Default + MaybeSerializeDebug;
+	type LocalSessionKey: Parameter + Default + MaybeSerializeDebug;
+
+	// Convert to LocalSessionKey.
+	type ConvertLocalSessionKey: Convert<Self::SessionKey, Self::LocalSessionKey>;
 
 	/// The event type of this module.
 	type Event: From<Event<Self>> + Into<<Self as system::Trait>::Event>;
@@ -139,30 +142,30 @@ pub trait Trait: system::Trait {
 // TODO: remove shim
 // https://github.com/paritytech/substrate/issues/1614
 #[derive(Encode, Decode)]
-pub struct OldStoredPendingChange<N, SessionKey> {
+pub struct OldStoredPendingChange<N, LocalSessionKey> {
 	/// The block number this was scheduled at.
 	pub scheduled_at: N,
 	/// The delay in blocks until it will be applied.
 	pub delay: N,
 	/// The next authority set.
-	pub next_authorities: Vec<(SessionKey, u64)>,
+	pub next_authorities: Vec<(LocalSessionKey, u64)>,
 }
 
 /// A stored pending change.
 #[derive(Encode)]
-pub struct StoredPendingChange<N, SessionKey> {
+pub struct StoredPendingChange<N, LocalSessionKey> {
 	/// The block number this was scheduled at.
 	pub scheduled_at: N,
 	/// The delay in blocks until it will be applied.
 	pub delay: N,
 	/// The next authority set.
-	pub next_authorities: Vec<(SessionKey, u64)>,
+	pub next_authorities: Vec<(LocalSessionKey, u64)>,
 	/// If defined it means the change was forced and the given block number
 	/// indicates the median last finalized block when the change was signaled.
 	pub forced: Option<N>,
 }
 
-impl<N: Decode, SessionKey: Decode> Decode for StoredPendingChange<N, SessionKey> {
+impl<N: Decode, LocalSessionKey: Decode> Decode for StoredPendingChange<N, LocalSessionKey> {
 	fn decode<I: codec::Input>(value: &mut I) -> Option<Self> {
 		let old = OldStoredPendingChange::decode(value)?;
 		let forced = <Option<N>>::decode(value).unwrap_or(None);
@@ -177,21 +180,21 @@ impl<N: Decode, SessionKey: Decode> Decode for StoredPendingChange<N, SessionKey
 }
 
 decl_event!(
-	pub enum Event<T> where <T as Trait>::SessionKey {
+	pub enum Event<T> where <T as Trait>::LocalSessionKey {
 		/// New authority set has been applied.
-		NewAuthorities(Vec<(SessionKey, u64)>),
+		NewAuthorities(Vec<(LocalSessionKey, u64)>),
 	}
 );
 
 decl_storage! {
 	trait Store for Module<T: Trait> as GrandpaFinality {
 		// Pending change: (signaled at, scheduled change).
-		PendingChange get(pending_change): Option<StoredPendingChange<T::BlockNumber, T::SessionKey>>;
+		PendingChange get(pending_change): Option<StoredPendingChange<T::BlockNumber, T::LocalSessionKey>>;
 		// next block number where we can force a change.
 		NextForced get(next_forced): Option<T::BlockNumber>;
 	}
 	add_extra_genesis {
-		config(authorities): Vec<(T::SessionKey, u64)>;
+		config(authorities): Vec<(T::LocalSessionKey, u64)>;
 
 		build(|storage: &mut primitives::StorageOverlay, _: &mut primitives::ChildrenStorageOverlay, config: &GenesisConfig<T>| {
 			use codec::{Encode, KeyedVec};
@@ -242,7 +245,7 @@ decl_module! {
 					Self::deposit_event(
 						RawEvent::NewAuthorities(pending_change.next_authorities.clone())
 					);
-					<AuthorityStorageVec<T::SessionKey>>::set_items(pending_change.next_authorities);
+					<AuthorityStorageVec<T::LocalSessionKey>>::set_items(pending_change.next_authorities);
 					<PendingChange<T>>::kill();
 				}
 			}
@@ -252,8 +255,8 @@ decl_module! {
 
 impl<T: Trait> Module<T> {
 	/// Get the current set of authorities, along with their respective weights.
-	pub fn grandpa_authorities() -> Vec<(T::SessionKey, u64)> {
-		<AuthorityStorageVec<T::SessionKey>>::items()
+	pub fn grandpa_authorities() -> Vec<(T::LocalSessionKey, u64)> {
+		<AuthorityStorageVec<T::LocalSessionKey>>::items()
 	}
 
 	/// Schedule a change in the authorities.
@@ -271,7 +274,7 @@ impl<T: Trait> Module<T> {
 	/// No change should be signaled while any change is pending. Returns
 	/// an error if a change is already pending.
 	pub fn schedule_change(
-		next_authorities: Vec<(T::SessionKey, u64)>,
+		next_authorities: Vec<(T::LocalSessionKey, u64)>,
 		in_blocks: T::BlockNumber,
 		forced: Option<T::BlockNumber>,
 	) -> Result {
@@ -307,7 +310,7 @@ impl<T: Trait> Module<T> {
 	}
 }
 
-impl<T: Trait> Module<T> where AuthorityId: core::convert::From<<T as Trait>::SessionKey> {
+impl<T: Trait> Module<T> where AuthorityId: core::convert::From<<T as Trait>::LocalSessionKey> {
 	/// See if the digest contains any standard scheduled change.
 	pub fn scrape_digest_change(log: &Log<T>)
 		-> Option<ScheduledChange<T::BlockNumber>>
@@ -337,17 +340,15 @@ impl<T> Default for SyncedAuthorities<T> {
 	}
 }
 
-impl<X, T> session::OnSessionChange<X> for SyncedAuthorities<T> where
-	T: Trait + consensus::Trait<SessionKey=<T as Trait>::SessionKey>,
-	<T as consensus::Trait>::Log: From<consensus::RawLog<<T as Trait>::SessionKey>>
+impl<X, T: Trait> session::OnSessionChange<X> for SyncedAuthorities<T> where
 {
 	fn on_session_change(_: X, _: bool) {
 		use primitives::traits::Zero;
 
 		let next_authorities = <consensus::Module<T>>::authorities()
 			.into_iter()
-			.map(|key| (key, 1)) // evenly-weighted.
-			.collect::<Vec<(<T as Trait>::SessionKey, u64)>>();
+			.map(|key| (T::ConvertLocalSessionKey::convert(key), 1)) // evenly-weighted.
+			.collect::<Vec<(<T as Trait>::LocalSessionKey, u64)>>();
 
 		// instant changes
 		let last_authorities = <Module<T>>::grandpa_authorities();
@@ -357,9 +358,7 @@ impl<X, T> session::OnSessionChange<X> for SyncedAuthorities<T> where
 	}
 }
 
-impl<T> finality_tracker::OnFinalizationStalled<T::BlockNumber> for SyncedAuthorities<T> where
-	T: Trait + consensus::Trait<SessionKey=<T as Trait>::SessionKey>,
-	<T as consensus::Trait>::Log: From<consensus::RawLog<<T as Trait>::SessionKey>>,
+impl<T: Trait> finality_tracker::OnFinalizationStalled<T::BlockNumber> for SyncedAuthorities<T> where
 	T: finality_tracker::Trait,
 {
 	fn on_stalled(further_wait: T::BlockNumber) {
@@ -369,8 +368,8 @@ impl<T> finality_tracker::OnFinalizationStalled<T::BlockNumber> for SyncedAuthor
 
 		let next_authorities = <consensus::Module<T>>::authorities()
 			.into_iter()
-			.map(|key| (key, 1)) // evenly-weighted.
-			.collect::<Vec<(<T as Trait>::SessionKey, u64)>>();
+			.map(|key| (T::ConvertLocalSessionKey::convert(key), 1)) // evenly-weighted.
+			.collect::<Vec<(<T as Trait>::LocalSessionKey, u64)>>();
 
 		let median = <finality_tracker::Module<T>>::median();
 
diff --git a/srml/grandpa/src/mock.rs b/srml/grandpa/src/mock.rs
index 4405604ab19c0..e6b93aa05c467 100644
--- a/srml/grandpa/src/mock.rs
+++ b/srml/grandpa/src/mock.rs
@@ -39,9 +39,26 @@ impl From<RawLog<u64, u64>> for DigestItem {
 // Workaround for https://github.com/rust-lang/rust/issues/26925 . Remove when sorted.
 #[derive(Clone, PartialEq, Eq, Debug, Decode, Encode)]
 pub struct Test;
+impl timestamp::Trait for Test {
+	type Moment = u64;
+	type OnTimestampSet = ();
+}
+impl consensus::Trait for Test {
+	type Log = DigestItem;
+	type SessionKey = substrate_primitives::sr25519::Public;
+	type InherentOfflineReport = ();
+}
+impl session::Trait for Test {
+	type ConvertAccountIdToSessionKey = ();
+	type OnSessionChange = ();
+	type OnDisable = ();
+	type CheckRotateSession = session::AuraCheckRotateSession<Self>;
+	type Event = TestEvent;
+}
 impl Trait for Test {
 	type Log = DigestItem;
-	type SessionKey = u64;
+	type LocalSessionKey = u64;
+	type ConvertLocalSessionKey = ();
 	type Event = TestEvent;
 }
 impl system::Trait for Test {
@@ -65,6 +82,7 @@ mod grandpa {
 impl_outer_event!{
 	pub enum TestEvent for Test {
 		grandpa<T>,
+		session<T>,
 	}
 }
 
diff --git a/srml/session/src/lib.rs b/srml/session/src/lib.rs
index d13795e4bb09c..1f5f965ba4056 100644
--- a/srml/session/src/lib.rs
+++ b/srml/session/src/lib.rs
@@ -329,13 +329,15 @@ impl<T: Trait> OnFreeBalanceZero<T::AccountId> for Module<T> {
 #[cfg(test)]
 mod tests {
 	use super::*;
+	use serde::{Deserialize, Serialize};
 	use std::cell::RefCell;
 	use srml_support::{impl_outer_origin, assert_ok};
 	use runtime_io::with_externalities;
-	use substrate_primitives::{H256, Blake2Hasher};
+	use substrate_primitives::{H256, U256, Blake2Hasher, ed25519, sr25519};
+	use parity_codec::{Decode, Encode};
 	use primitives::BuildStorage;
 	use primitives::traits::{BlakeTwo256, IdentityLookup};
-	use primitives::testing::{Digest, DigestItem, Header, UintAuthorityId, ConvertUintAuthorityId};
+	use primitives::testing::{Digest, DigestItem, Header};
 
 	impl_outer_origin!{
 		pub enum Origin for Test {}
@@ -356,9 +358,40 @@ mod tests {
 	pub struct Test;
 	impl consensus::Trait for Test {
 		type Log = DigestItem;
-		type SessionKey = UintAuthorityId;
+		type SessionKey = TestSessionKey;
 		type InherentOfflineReport = ();
 	}
+
+	#[derive(Clone, Debug, Default, PartialEq, Eq, Encode, Decode, Serialize, Deserialize)]
+	pub struct TestSessionKey(u64, u64);
+
+	impl From<TestSessionKey> for sr25519::Public {
+		fn from(key: TestSessionKey) -> Self {
+			let bytes: [u8; 32] = H256::from_low_u64_be(key.0).into();
+			Self(bytes)
+		}
+	}
+
+	impl From<TestSessionKey> for ed25519::Public {
+		fn from(key: TestSessionKey) -> Self {
+			let bytes: [u8; 32] = H256::from_low_u64_be(key.1).into();
+			Self(bytes)
+		}
+	}
+
+	pub struct ConvertU64ToTestSessionKey;
+	impl Convert<u64, Option<TestSessionKey>> for ConvertU64ToTestSessionKey {
+		fn convert(a: u64) -> Option<TestSessionKey> {
+				Some(TestSessionKey::from(a))
+		}
+	}
+
+	impl From<u64> for TestSessionKey {
+		fn from(id: u64) -> Self {
+			Self(id, id + 100)
+		}
+	}
+
 	impl system::Trait for Test {
 		type Origin = Origin;
 		type Index = u64;
@@ -377,7 +410,7 @@ mod tests {
 		type OnTimestampSet = ();
 	}
 	impl Trait for Test {
-		type ConvertAccountIdToSessionKey = ConvertUintAuthorityId;
+		type ConvertAccountIdToSessionKey = ConvertU64ToTestSessionKey;
 		type OnSessionChange = TestOnSessionChange;
 		type Event = ();
 	}
@@ -390,7 +423,7 @@ mod tests {
 		let mut t = system::GenesisConfig::<Test>::default().build_storage().unwrap().0;
 		t.extend(consensus::GenesisConfig::<Test>{
 			code: vec![],
-			authorities: NEXT_VALIDATORS.with(|l| l.borrow().iter().cloned().map(UintAuthorityId).collect()),
+			authorities: NEXT_VALIDATORS.with(|l| l.borrow().iter().cloned().map(TestSessionKey::from).collect()),
 		}.build_storage().unwrap().0);
 		t.extend(timestamp::GenesisConfig::<Test>{
 			minimum_period: 5,
@@ -403,10 +436,14 @@ mod tests {
 		runtime_io::TestExternalities::new(t)
 	}
 
+	fn account_ids_to_session_keys(account_ids: Vec<u64>) -> Vec<TestSessionKey> {
+		account_ids.into_iter().map(TestSessionKey::from).collect()
+	}
+
 	#[test]
 	fn simple_setup_should_work() {
 		with_externalities(&mut new_test_ext(), || {
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(3)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 3]));
 			assert_eq!(Session::length(), 2);
 			assert_eq!(Session::validators(), vec![1, 2, 3]);
 		});
@@ -419,19 +456,19 @@ mod tests {
 			assert_ok!(Session::force_new_session(false));
 			Session::check_rotate_session(1);
 			assert_eq!(Session::validators(), vec![1, 2]);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2]));
 
 			NEXT_VALIDATORS.with(|v| *v.borrow_mut() = vec![1, 2, 4]);
 			assert_ok!(Session::force_new_session(false));
 			Session::check_rotate_session(2);
 			assert_eq!(Session::validators(), vec![1, 2, 4]);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(4)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 4]));
 
 			NEXT_VALIDATORS.with(|v| *v.borrow_mut() = vec![1, 2, 3]);
 			assert_ok!(Session::force_new_session(false));
 			Session::check_rotate_session(3);
 			assert_eq!(Session::validators(), vec![1, 2, 3]);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(3)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 3]));
 		});
 	}
 
@@ -525,25 +562,25 @@ mod tests {
 			// Block 1: No change
 			System::set_block_number(1);
 			Session::check_rotate_session(1);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(3)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 3]));
 
 			// Block 2: Session rollover, but no change.
 			System::set_block_number(2);
 			Session::check_rotate_session(2);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(3)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 3]));
 
 			// Block 3: Set new key for validator 2; no visible change.
 			System::set_block_number(3);
-			assert_ok!(Session::set_key(Origin::signed(2), UintAuthorityId(5)));
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(3)]);
+			assert_ok!(Session::set_key(Origin::signed(2), TestSessionKey::from(5)));
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 3]));
 
 			Session::check_rotate_session(3);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(2), UintAuthorityId(3)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 2, 3]));
 
 			// Block 4: Session rollover, authority 2 changes.
 			System::set_block_number(4);
 			Session::check_rotate_session(4);
-			assert_eq!(Consensus::authorities(), vec![UintAuthorityId(1), UintAuthorityId(5), UintAuthorityId(3)]);
+			assert_eq!(Consensus::authorities(), account_ids_to_session_keys(vec![1, 5, 3]));
 		});
 	}
 }