diff --git a/src/crypto/memory_stores.rs b/src/crypto/memory_stores.rs
index 413e1e06..2d9f5e11 100644
--- a/src/crypto/memory_stores.rs
+++ b/src/crypto/memory_stores.rs
@@ -22,19 +22,22 @@ use super::device::Device;
 use super::olm::{InboundGroupSession, Session};
 use crate::identifiers::{DeviceId, RoomId, UserId};
 
+/// In-memory store for Olm Sessions.
 #[derive(Debug)]
 pub struct SessionStore {
     entries: HashMap<String, Arc<Mutex<Vec<Session>>>>,
 }
 
 impl SessionStore {
+    /// Create a new empty Session store.
     pub fn new() -> Self {
         SessionStore {
             entries: HashMap::new(),
         }
     }
 
-    pub async fn add(&mut self, session: Session) -> Session {
+    /// Add a session to the store.
+    pub async fn add(&mut self, session: Session) {
         if !self.entries.contains_key(&*session.sender_key) {
             self.entries.insert(
                 session.sender_key.to_string(),
@@ -42,15 +45,15 @@ impl SessionStore {
             );
         }
         let sessions = self.entries.get_mut(&*session.sender_key).unwrap();
-        sessions.lock().await.push(session.clone());
-
-        session
+        sessions.lock().await.push(session);
     }
 
+    /// Get all the sessions that belong to the given sender key.
     pub fn get(&self, sender_key: &str) -> Option<Arc<Mutex<Vec<Session>>>> {
         self.entries.get(sender_key).cloned()
     }
 
+    /// Add a list of sessions belonging to the sender key.
     pub fn set_for_sender(&mut self, sender_key: &str, sessions: Vec<Session>) {
         self.entries
             .insert(sender_key.to_owned(), Arc::new(Mutex::new(sessions)));
@@ -58,17 +61,20 @@ impl SessionStore {
 }
 
 #[derive(Debug)]
+/// In-memory store that houlds inbound group sessions.
 pub struct GroupSessionStore {
     entries: HashMap<RoomId, HashMap<String, HashMap<String, InboundGroupSession>>>,
 }
 
 impl GroupSessionStore {
+    /// Create a new empty store.
     pub fn new() -> Self {
         GroupSessionStore {
             entries: HashMap::new(),
         }
     }
 
+    /// Add a inbound group session to the store.
     pub fn add(&mut self, session: InboundGroupSession) -> bool {
         if !self.entries.contains_key(&session.room_id) {
             let room_id = &*session.room_id;
@@ -88,6 +94,14 @@ impl GroupSessionStore {
         ret.is_some()
     }
 
+    /// Get a inbound group session from our store.
+    ///
+    /// # Arguments
+    /// * `room_id` - The room id of the room that the session belongs to.
+    ///
+    /// * `sender_key` - The sender key that sent us the session.
+    ///
+    /// * `session_id` - The unique id of the session.
     pub fn get(
         &self,
         room_id: &RoomId,
@@ -158,3 +172,86 @@ impl DeviceStore {
         }
     }
 }
+
+#[cfg(test)]
+mod test {
+    use std::collections::HashMap;
+    use std::convert::TryFrom;
+
+    use crate::api::r0::keys::SignedKey;
+    use crate::crypto::memory_stores::{DeviceStore, GroupSessionStore, SessionStore};
+    use crate::crypto::olm::{Account, InboundGroupSession, OutboundGroupSession, Session};
+    use crate::identifiers::RoomId;
+
+    async fn get_account_and_session() -> (Account, Session) {
+        let alice = Account::new();
+
+        let bob = Account::new();
+
+        bob.generate_one_time_keys(1).await;
+        let one_time_key = bob
+            .one_time_keys()
+            .await
+            .curve25519()
+            .iter()
+            .nth(0)
+            .unwrap()
+            .1
+            .to_owned();
+        let one_time_key = SignedKey {
+            key: one_time_key,
+            signatures: HashMap::new(),
+        };
+        let sender_key = bob.identity_keys().curve25519().to_owned();
+        let session = alice
+            .create_outbound_session(&sender_key, &one_time_key)
+            .await
+            .unwrap();
+
+        (alice, session)
+    }
+
+    #[tokio::test]
+    async fn test_session_store() {
+        let (account, session) = get_account_and_session().await;
+
+        let mut store = SessionStore::new();
+        store.add(session.clone()).await;
+
+        let sessions = store.get(&session.sender_key).unwrap();
+        let sessions = sessions.lock().await;
+
+        let loaded_session = &sessions[0];
+
+        assert_eq!(&session, loaded_session);
+    }
+
+    #[tokio::test]
+    async fn test_group_session_store() {
+        let alice = Account::new();
+        let room_id = RoomId::try_from("!test:localhost").unwrap();
+
+        let outbound = OutboundGroupSession::new(&room_id);
+
+        assert_eq!(0, outbound.message_index().await);
+        assert!(!outbound.shared());
+        outbound.mark_as_shared();
+        assert!(outbound.shared());
+
+        let inbound = InboundGroupSession::new(
+            "test_key",
+            "test_key",
+            &room_id,
+            outbound.session_key().await,
+        )
+        .unwrap();
+
+        let mut store = GroupSessionStore::new();
+        store.add(inbound.clone());
+
+        let loaded_session = store
+            .get(&room_id, "test_key", outbound.session_id())
+            .unwrap();
+        assert_eq!(inbound, loaded_session);
+    }
+}
diff --git a/src/crypto/olm.rs b/src/crypto/olm.rs
index 72e28b2d..8d160bbd 100644
--- a/src/crypto/olm.rs
+++ b/src/crypto/olm.rs
@@ -497,6 +497,12 @@ impl fmt::Debug for InboundGroupSession {
     }
 }
 
+impl PartialEq for InboundGroupSession {
+    fn eq(&self, other: &Self) -> bool {
+        self.session_id() == other.session_id()
+    }
+}
+
 /// Outbound group session.
 ///
 /// Outbound group sessions are used to exchange room messages between a group
diff --git a/src/crypto/store/sqlite.rs b/src/crypto/store/sqlite.rs
index cc4aea7c..99a859f4 100644
--- a/src/crypto/store/sqlite.rs
+++ b/src/crypto/store/sqlite.rs
@@ -350,7 +350,7 @@ impl CryptoStore for SqliteStore {
     }
 
     async fn add_and_save_session(&mut self, session: Session) -> Result<()> {
-        let session = self.sessions.add(session).await;
+        self.sessions.add(session.clone()).await;
         self.save_session(session).await?;
         Ok(())
     }
@@ -435,9 +435,7 @@ mod test {
     use olm_rs::outbound_group_session::OlmOutboundGroupSession;
     use ruma_client_api::r0::keys::SignedKey;
     use std::collections::HashMap;
-    use std::sync::Arc;
     use tempfile::tempdir;
-    use tokio::sync::Mutex;
 
     use super::{
         Account, CryptoStore, InboundGroupSession, RoomId, Session, SqliteStore, TryFrom, UserId,