diff --git a/spring-cloud-function-adapters/spring-cloud-function-adapter-aws/src/main/java/org/springframework/cloud/function/adapter/aws/CustomRuntimeEventLoop.java b/spring-cloud-function-adapters/spring-cloud-function-adapter-aws/src/main/java/org/springframework/cloud/function/adapter/aws/CustomRuntimeEventLoop.java
index 42d6e2fce..43cec472d 100644
--- a/spring-cloud-function-adapters/spring-cloud-function-adapter-aws/src/main/java/org/springframework/cloud/function/adapter/aws/CustomRuntimeEventLoop.java
+++ b/spring-cloud-function-adapters/spring-cloud-function-adapter-aws/src/main/java/org/springframework/cloud/function/adapter/aws/CustomRuntimeEventLoop.java
@@ -16,12 +16,15 @@
 
 package org.springframework.cloud.function.adapter.aws;
 
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.net.SocketException;
 import java.net.URI;
 import java.nio.charset.StandardCharsets;
 import java.text.MessageFormat;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.concurrent.ExecutorService;
@@ -30,6 +33,7 @@ import java.util.concurrent.Executors;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+
 import org.springframework.cloud.function.context.FunctionCatalog;
 import org.springframework.cloud.function.context.catalog.SimpleFunctionRegistry.FunctionInvocationWrapper;
 import org.springframework.cloud.function.json.JsonMapper;
@@ -45,6 +49,8 @@ import org.springframework.messaging.MessageHeaders;
 import org.springframework.util.Assert;
 import org.springframework.web.client.RestTemplate;
 
+
+
 import static org.apache.http.HttpHeaders.USER_AGENT;
 
 /**
@@ -61,6 +67,7 @@ public final class CustomRuntimeEventLoop implements SmartLifecycle {
 	private static Log logger = LogFactory.getLog(CustomRuntimeEventLoop.class);
 
 	static final String LAMBDA_VERSION_DATE = "2018-06-01";
+	private static final String LAMBDA_ERROR_URL_TEMPLATE = "http://{0}/{1}/runtime/invocation/{2}/error";
 	private static final String LAMBDA_RUNTIME_URL_TEMPLATE = "http://{0}/{1}/runtime/invocation/next";
 	private static final String LAMBDA_INVOCATION_URL_TEMPLATE = "http://{0}/{1}/runtime/invocation/{2}/response";
 	private static final String USER_AGENT_VALUE = String.format(
@@ -141,19 +148,46 @@ public final class CustomRuntimeEventLoop implements SmartLifecycle {
 				String invocationUrl = MessageFormat
 						.format(LAMBDA_INVOCATION_URL_TEMPLATE, runtimeApi, LAMBDA_VERSION_DATE, requestId);
 
-				Message<byte[]> responseMessage = (Message<byte[]>) function.apply(eventMessage);
+				try {
+					Message<byte[]> responseMessage = (Message<byte[]>) function.apply(eventMessage);
 
-				if (responseMessage != null && logger.isDebugEnabled()) {
-					logger.debug("Reply from function: " + responseMessage);
+					if (responseMessage != null && logger.isDebugEnabled()) {
+						logger.debug("Reply from function: " + responseMessage);
+					}
+
+					byte[] outputBody = AWSLambdaUtils.generateOutput(eventMessage, responseMessage, mapper, function.getOutputType());
+					ResponseEntity<Object> result = rest.exchange(RequestEntity.post(URI.create(invocationUrl))
+						.header(USER_AGENT, USER_AGENT_VALUE)
+						.body(outputBody), Object.class);
+
+					if (logger.isInfoEnabled()) {
+						logger.info("Result POST status: " + result.getStatusCode());
+					}
 				}
-
-				byte[] outputBody = AWSLambdaUtils.generateOutput(eventMessage, responseMessage, mapper, function.getOutputType());
-				ResponseEntity<Object> result = rest.exchange(RequestEntity.post(URI.create(invocationUrl))
-					.header(USER_AGENT, USER_AGENT_VALUE)
-					.body(outputBody), Object.class);
-
-				if (logger.isInfoEnabled()) {
-					logger.info("Result POST status: " + result.getStatusCode());
+				catch (Exception e) {
+					String errorMessage = e.getMessage();
+					String errorType = e.getClass().getSimpleName();
+					StringWriter sw = new StringWriter();
+					PrintWriter pw = new PrintWriter(sw);
+					e.printStackTrace(pw);
+					String stackTrace = sw.toString();
+					Map<String, String> em = new HashMap<>();
+					em.put("errorMessage", errorMessage);
+					em.put("errorType", errorType);
+					em.put("stackTrace", stackTrace);
+					byte[] outputBody = mapper.toJson(em);
+					try {
+						String errorUrl = MessageFormat.format(LAMBDA_ERROR_URL_TEMPLATE, runtimeApi, LAMBDA_VERSION_DATE, requestId);
+						ResponseEntity<Object> result = rest.exchange(RequestEntity.post(URI.create(errorUrl))
+								.header(USER_AGENT, USER_AGENT_VALUE)
+								.body(outputBody), Object.class);
+						if (logger.isInfoEnabled()) {
+							logger.info("Result ERROR status: " + result.getStatusCode());
+						}
+					}
+					catch (Exception e2) {
+						throw new IllegalArgumentException("Failed to report error", e2);
+					}
 				}
 			}
 		}
diff --git a/spring-cloud-function-samples/function-sample-aws-custom/src/main/java/com/example/LambdaApplication.java b/spring-cloud-function-samples/function-sample-aws-custom/src/main/java/com/example/LambdaApplication.java
index 730053793..cea0dfab7 100644
--- a/spring-cloud-function-samples/function-sample-aws-custom/src/main/java/com/example/LambdaApplication.java
+++ b/spring-cloud-function-samples/function-sample-aws-custom/src/main/java/com/example/LambdaApplication.java
@@ -21,6 +21,9 @@ public class LambdaApplication
 	public Function<String, String> uppercase() {
 		return value -> {
 			logger.info("Processing: " + value);
+			if (value.equals("error")) {
+				throw new IllegalArgumentException("Intentional");
+			}
 			return value.toUpperCase();
 		};
 	}
diff --git a/spring-cloud-function-samples/function-sample/src/test/java/com/example/WebTestClientTests.java b/spring-cloud-function-samples/function-sample/src/test/java/com/example/WebTestClientTests.java
index c74216e7b..9e4cfc703 100644
--- a/spring-cloud-function-samples/function-sample/src/test/java/com/example/WebTestClientTests.java
+++ b/spring-cloud-function-samples/function-sample/src/test/java/com/example/WebTestClientTests.java
@@ -19,12 +19,6 @@ public class WebTestClientTests {
 	@Autowired
 	private WebTestClient client;
 
-	@Test
-	public void words() {
-		client.get().uri("/words").exchange()
-			.expectStatus().isOk().expectBody(String.class).isEqualTo("[\"foo\",\"bar\"]");
-	}
-
 	@Test
 	public void uppercase() {
 		client.post().uri("/uppercase").body(Mono.just("foo"), String.class).exchange()