diff --git a/spring-session-core/src/main/java/org/springframework/session/MapReactorSessionRepository.java b/spring-session-core/src/main/java/org/springframework/session/MapReactorSessionRepository.java
new file mode 100644
index 00000000..a2b4bc0b
--- /dev/null
+++ b/spring-session-core/src/main/java/org/springframework/session/MapReactorSessionRepository.java
@@ -0,0 +1,150 @@
+/*
+ * Copyright 2014-2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.session;
+
+import org.springframework.session.events.SessionDeletedEvent;
+import org.springframework.session.events.SessionExpiredEvent;
+import reactor.core.publisher.Mono;
+
+import java.time.Duration;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * A {@link SessionRepository} backed by a {@link Map} and that uses a
+ * {@link MapSession}. By default a {@link ConcurrentHashMap} is
+ * used, but a custom {@link Map} can be injected to use distributed maps
+ * provided by NoSQL stores like Redis and Hazelcast.
+ *
+ * <p>
+ * The implementation does NOT support firing {@link SessionDeletedEvent} or
+ * {@link SessionExpiredEvent}.
+ * </p>
+ *
+ * @author Rob Winch
+ * @since 2.0
+ */
+public class MapReactorSessionRepository implements ReactorSessionRepository<Session> {
+	/**
+	 * If non-null, this value is used to override
+	 * {@link Session#setMaxInactiveInterval(Duration)}.
+	 */
+	private Integer defaultMaxInactiveInterval;
+
+	private final Map<String, Session> sessions;
+
+	/**
+	 * Creates an instance backed by a {@link ConcurrentHashMap}.
+	 */
+	public MapReactorSessionRepository() {
+		this(new ConcurrentHashMap<>());
+	}
+
+	/**
+	 * Creates a new instance backed by the provided {@link Map}. This allows
+	 * injecting a distributed {@link Map}.
+	 *
+	 * @param sessions the {@link Map} to use. Cannot be null.
+	 */
+	public MapReactorSessionRepository(Map<String, Session> sessions) {
+		if (sessions == null) {
+			throw new IllegalArgumentException("sessions cannot be null");
+		}
+		this.sessions = sessions;
+	}
+
+	/**
+	 * Creates a new instance backed by the provided {@link Map}. This allows
+	 * injecting a distributed {@link Map}.
+	 *
+	 * @param sessions the {@link Map} to use. Cannot be null.
+	 */
+	public MapReactorSessionRepository(Session... sessions) {
+		if (sessions == null) {
+			throw new IllegalArgumentException("sessions cannot be null");
+		}
+		this.sessions = new ConcurrentHashMap<>();
+		for(Session session : sessions) {
+			this.performSave(session);
+		}
+	}
+
+	/**
+	 * Creates a new instance backed by the provided {@link Map}. This allows
+	 * injecting a distributed {@link Map}.
+	 *
+	 * @param sessions the {@link Map} to use. Cannot be null.
+	 */
+	public MapReactorSessionRepository(Iterable<Session> sessions) {
+		if (sessions == null) {
+			throw new IllegalArgumentException("sessions cannot be null");
+		}
+		this.sessions = new ConcurrentHashMap<>();
+		for(Session session : sessions) {
+			this.performSave(session);
+		}
+	}
+
+	/**
+	 * If non-null, this value is used to override
+	 * {@link Session#setMaxInactiveInterval(Duration)}.
+	 * @param defaultMaxInactiveInterval the number of seconds that the {@link Session}
+	 * should be kept alive between client requests.
+	 */
+	public void setDefaultMaxInactiveInterval(int defaultMaxInactiveInterval) {
+		this.defaultMaxInactiveInterval = Integer.valueOf(defaultMaxInactiveInterval);
+	}
+
+	public Mono<Void> save(Session session) {
+		return Mono.fromRunnable(() -> performSave(session));
+	}
+
+	private void performSave(Session session) {
+		this.sessions.put(session.getId(), new MapSession(session));
+	}
+
+	public Mono<Session> findById(String id) {
+		return Mono.defer(() -> {
+			Session saved = this.sessions.get(id);
+			if (saved == null) {
+				return Mono.empty();
+			}
+			if (saved.isExpired()) {
+				delete(saved.getId());
+				return Mono.empty();
+			}
+			return Mono.just(new MapSession(saved));
+		});
+	}
+
+	public Mono<Void> delete(String id) {
+		return Mono.fromRunnable(() -> this.sessions.remove(id));
+	}
+
+	public Mono<Session> createSession() {
+		return Mono.defer(() -> {
+			Session result = new MapSession();
+			if (this.defaultMaxInactiveInterval != null) {
+				result.setMaxInactiveInterval(
+						Duration.ofSeconds(this.defaultMaxInactiveInterval));
+			}
+			return Mono.just(result);
+		});
+	}
+}
diff --git a/spring-session-core/src/test/java/org/springframework/session/MapReactorSessionRepositoryTests.java b/spring-session-core/src/test/java/org/springframework/session/MapReactorSessionRepositoryTests.java
new file mode 100644
index 00000000..3da5b976
--- /dev/null
+++ b/spring-session-core/src/test/java/org/springframework/session/MapReactorSessionRepositoryTests.java
@@ -0,0 +1,148 @@
+/*
+ * Copyright 2014-2017 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.session;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import java.time.Duration;
+import java.time.Instant;
+import java.time.temporal.ChronoUnit;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Rob Winch
+ * @since 2.0
+ */
+public class MapReactorSessionRepositoryTests {
+	MapReactorSessionRepository repository;
+
+	MapSession session;
+
+	@Before
+	public void setup() {
+		this.repository = new MapReactorSessionRepository();
+		this.session = new MapSession("session-id");
+	}
+
+	@Test
+	public void constructorVarargsThenFound() {
+		this.repository = new MapReactorSessionRepository(this.session);
+
+		Session findByIdSession = this.repository.findById(this.session.getId()).block();
+		assertThat(findByIdSession).isNotNull();
+		assertThat(findByIdSession.getId()).isEqualTo(this.session.getId());
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void constructorVarargsWhenNullThenThrowsIllegalArgumentException() {
+		Session[] sessions = null;
+		new MapReactorSessionRepository(sessions);
+	}
+
+	@Test
+	public void constructorIterableThenFound() {
+		this.repository = new MapReactorSessionRepository(Arrays.asList(this.session));
+
+		Session findByIdSession = this.repository.findById(this.session.getId()).block();
+		assertThat(findByIdSession).isNotNull();
+		assertThat(findByIdSession.getId()).isEqualTo(this.session.getId());
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void constructorIterableWhenNullThenThrowsIllegalArgumentException() {
+		Iterable<Session> sessions = null;
+		new MapReactorSessionRepository(sessions);
+	}
+
+	@Test
+	public void constructorMapThenFound() {
+		Map<String, Session> sessions = new HashMap<>();
+		sessions.put(this.session.getId(), this.session);
+		this.repository = new MapReactorSessionRepository(sessions);
+
+		Session findByIdSession = this.repository.findById(this.session.getId()).block();
+		assertThat(findByIdSession).isNotNull();
+		assertThat(findByIdSession.getId()).isEqualTo(this.session.getId());
+	}
+
+	@Test(expected = IllegalArgumentException.class)
+	public void constructorMapWhenNullThenThrowsIllegalArgumentException() {
+		Map<String,Session> sessions = null;
+		new MapReactorSessionRepository(sessions);
+	}
+
+	@Test
+	public void saveWhenNoSubscribersThenNotFound() {
+		this.repository.save(this.session);
+
+		assertThat(this.repository.findById(this.session.getId()).block()).isNull();
+	}
+
+	@Test
+	public void saveWhenSubscriberThenFound() {
+		this.repository.save(this.session).block();
+
+		Session findByIdSession = this.repository.findById(this.session.getId()).block();
+		assertThat(findByIdSession).isNotNull();
+		assertThat(findByIdSession.getId()).isEqualTo(this.session.getId());
+	}
+
+	@Test
+	public void findByIdWhenNotExpiredThenFound() {
+		this.repository = new MapReactorSessionRepository(this.session);
+
+		Session findByIdSession = this.repository.findById(this.session.getId()).block();
+		assertThat(findByIdSession).isNotNull();
+		assertThat(findByIdSession.getId()).isEqualTo(this.session.getId());
+	}
+
+	@Test
+	public void findByIdWhenExpiredThenEmpty() {
+		this.session.setMaxInactiveInterval(Duration.ofSeconds(1));
+		this.session.setLastAccessedTime(Instant.now().minus(5, ChronoUnit.MINUTES));
+		this.repository = new MapReactorSessionRepository(Arrays.asList(this.session));
+
+		assertThat(this.repository.findById(this.session.getId()).block()).isNull();
+	}
+
+	@Test
+	public void createSessionWhenDefaultMaxInactiveIntervalThenDefaultMaxInactiveInterval() {
+		Session session = this.repository.createSession().block();
+
+		assertThat(session).isInstanceOf(MapSession.class);
+		assertThat(session.getMaxInactiveInterval())
+				.isEqualTo(new MapSession().getMaxInactiveInterval());
+	}
+
+	@Test
+	public void createSessionWhenCustomMaxInactiveIntervalThenCustomMaxInactiveInterval() {
+		final Duration expectedMaxInterval = new MapSession().getMaxInactiveInterval()
+				.plusSeconds(10);
+		this.repository.setDefaultMaxInactiveInterval(
+				(int) expectedMaxInterval.getSeconds());
+
+		Session session = this.repository.createSession().block();
+
+		assertThat(session.getMaxInactiveInterval())
+				.isEqualTo(expectedMaxInterval);
+	}
+}
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