diff --git a/substrate/Cargo.lock b/substrate/Cargo.lock
index e1d9a49793..7e77f3003b 100644
--- a/substrate/Cargo.lock
+++ b/substrate/Cargo.lock
@@ -2365,6 +2365,7 @@ dependencies = [
  "srml-treasury 2.0.0",
  "substrate-client 2.0.0",
  "substrate-consensus-babe-primitives 2.0.0",
+ "substrate-consensus-common-primitives 2.0.0",
  "substrate-keyring 2.0.0",
  "substrate-offchain-primitives 2.0.0",
  "substrate-primitives 2.0.0",
@@ -4385,6 +4386,16 @@ dependencies = [
  "substrate-test-runtime-client 2.0.0",
 ]
 
+[[package]]
+name = "substrate-consensus-common-primitives"
+version = "2.0.0"
+dependencies = [
+ "parity-codec 4.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sr-primitives 2.0.0",
+ "sr-std 2.0.0",
+ "substrate-client 2.0.0",
+]
+
 [[package]]
 name = "substrate-consensus-rhd"
 version = "2.0.0"
diff --git a/substrate/core/consensus/common/primitives/Cargo.toml b/substrate/core/consensus/common/primitives/Cargo.toml
new file mode 100644
index 0000000000..154863eed5
--- /dev/null
+++ b/substrate/core/consensus/common/primitives/Cargo.toml
@@ -0,0 +1,21 @@
+[package]
+name = "substrate-consensus-common-primitives"
+version = "2.0.0"
+authors = ["Parity Technologies <admin@parity.io>"]
+description = "Common consensus primitives"
+edition = "2018"
+
+[dependencies]
+parity-codec = { version = "4.1.1", default-features = false }
+client = { package = "substrate-client", path = "../../../client", default-features = false }
+sr-primitives = { package = "sr-primitives", path = "../../../sr-primitives", default-features = false }
+rstd = { package = "sr-std", path = "../../../sr-std", default-features = false }
+
+[features]
+default = ["std"]
+std = [
+    "rstd/std",
+    "client/std",
+    "parity-codec/std",
+    "sr-primitives/std"
+]
diff --git a/substrate/core/consensus/common/primitives/src/lib.rs b/substrate/core/consensus/common/primitives/src/lib.rs
new file mode 100644
index 0000000000..47c4371721
--- /dev/null
+++ b/substrate/core/consensus/common/primitives/src/lib.rs
@@ -0,0 +1,31 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Common consensus primitives.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+use parity_codec::Codec;
+use client::decl_runtime_apis;
+use rstd::vec::Vec;
+
+decl_runtime_apis! {
+	/// Common consensus runtime api.
+	pub trait ConsensusApi<AuthorityId: Codec> {
+		/// Returns the set of authorities of the currently active consensus mechanism.
+		fn authorities() -> Vec<AuthorityId>;
+	}
+}
diff --git a/substrate/node/runtime/Cargo.toml b/substrate/node/runtime/Cargo.toml
index eca7c9ebb7..9c52125fe8 100644
--- a/substrate/node/runtime/Cargo.toml
+++ b/substrate/node/runtime/Cargo.toml
@@ -19,6 +19,7 @@ support = { package = "srml-support", path = "../../srml/support", default-featu
 authorship = { package = "srml-authorship", path = "../../srml/authorship", default-features = false }
 babe = { package = "srml-babe", path = "../../srml/babe", default-features = false }
 babe-primitives = { package = "substrate-consensus-babe-primitives", path = "../../core/consensus/babe/primitives", default-features = false }
+consensus-primitives = { package = "substrate-consensus-common-primitives", path = "../../core/consensus/common/primitives", default-features = false }
 balances = { package = "srml-balances", path = "../../srml/balances", default-features = false }
 contracts = { package = "srml-contracts", path = "../../srml/contracts", default-features = false }
 collective = { package = "srml-collective", path = "../../srml/collective", default-features = false }
@@ -57,6 +58,7 @@ std = [
 	"authorship/std",
 	"babe/std",
 	"babe-primitives/std",
+	"consensus-primitives/std",
 	"balances/std",
 	"contracts/std",
 	"collective/std",
diff --git a/substrate/node/runtime/src/lib.rs b/substrate/node/runtime/src/lib.rs
index e657feebe9..f89b121afa 100644
--- a/substrate/node/runtime/src/lib.rs
+++ b/substrate/node/runtime/src/lib.rs
@@ -538,4 +538,10 @@ impl_runtime_apis! {
 			}
 		}
 	}
+
+	impl consensus_primitives::ConsensusApi<Block, babe_primitives::AuthorityId> for Runtime {
+		fn authorities() -> Vec<babe_primitives::AuthorityId> {
+			Babe::authorities().into_iter().map(|(a, _)| a).collect()
+		}
+	}
 }