diff --git a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionCatalogWrapper.java b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionCatalogWrapper.java
new file mode 100644
index 000000000..ced49d860
--- /dev/null
+++ b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionCatalogWrapper.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2018 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.cloud.stream.function;
+
+import org.springframework.cloud.function.context.FunctionCatalog;
+import org.springframework.util.Assert;
+
+/**
+ * @author David Turanski
+ **/
+public class FunctionCatalogWrapper {
+
+	private final FunctionCatalog catalog;
+
+	FunctionCatalogWrapper(FunctionCatalog catalog) {
+		this.catalog = catalog;
+	}
+
+	<T> T lookup(Class<T> functionType, String name) {
+		T function = catalog.lookup(functionType, name);
+		Assert.notNull(function, functionType == null ?
+			String.format("User provided Function '%s' cannot be located.", name) :
+			String.format("User provided %s '%s' cannot be located.", functionType.getSimpleName(), name));
+		return function;
+	}
+
+	<T> T lookup(String name) {
+		return lookup(null, name);
+	}
+
+}
diff --git a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java
index ff9ee83a1..8d5ef48e5 100644
--- a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java
+++ b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionConfiguration.java
@@ -34,7 +34,7 @@ import org.springframework.context.annotation.Configuration;
 public class FunctionConfiguration {
 
 	@Bean
-	public IntegrationFlowFunctionSupport functionSupport(FunctionCatalog functionCatalog,
+	public IntegrationFlowFunctionSupport functionSupport(FunctionCatalogWrapper functionCatalog,
 			FunctionInspector functionInspector, CompositeMessageConverterFactory messageConverterFactory,
 			FunctionProperties functionProperties) {
 
@@ -42,4 +42,9 @@ public class FunctionConfiguration {
 				functionProperties);
 	}
 
+	@Bean
+	public FunctionCatalogWrapper functionCatalogWrapper(FunctionCatalog catalog) {
+		return new FunctionCatalogWrapper(catalog);
+	}
+
 }
diff --git a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionInvoker.java b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionInvoker.java
index a0484211d..f9c8b7135 100644
--- a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionInvoker.java
+++ b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/FunctionInvoker.java
@@ -24,7 +24,6 @@ import org.apache.commons.logging.LogFactory;
 
 import reactor.core.publisher.Flux;
 
-import org.springframework.cloud.function.context.FunctionCatalog;
 import org.springframework.cloud.function.context.FunctionType;
 import org.springframework.cloud.function.context.catalog.FunctionInspector;
 import org.springframework.cloud.stream.converter.CompositeMessageConverterFactory;
@@ -35,6 +34,7 @@ import org.springframework.util.Assert;
 /**
  *
  * @author Oleg Zhurakousky
+ * @author David Turanski
  *
  * @param <I> the payload type of the input Message
  * @param <O> the payload type of the output Message
@@ -51,11 +51,10 @@ class FunctionInvoker<I, O> implements Function<Flux<Message<I>>, Flux<Message<O
 
 	private final CompositeMessageConverter messageConverter;
 
-	FunctionInvoker(String functionName, FunctionCatalog functionCatalog, FunctionInspector functionInspector,
+	FunctionInvoker(String functionName, FunctionCatalogWrapper functionCatalog, FunctionInspector functionInspector,
 			CompositeMessageConverterFactory compositeMessageConverterFactory) {
 		this.userFunction = functionCatalog.lookup(functionName);
 		Assert.isInstanceOf(Function.class, this.userFunction);
-		Assert.notNull(this.userFunction, "userFunction: " + functionName + " can not be located.");
 		this.messageConverter = compositeMessageConverterFactory.getMessageConverterForAllRegistered();
 		FunctionType functionType = functionInspector.getRegistration(this.userFunction).getType();
 		this.inputClass = functionType.getInputType();
diff --git a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/IntegrationFlowFunctionSupport.java b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/IntegrationFlowFunctionSupport.java
index fe1d1898a..f05e1ec88 100644
--- a/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/IntegrationFlowFunctionSupport.java
+++ b/spring-cloud-stream/src/main/java/org/springframework/cloud/stream/function/IntegrationFlowFunctionSupport.java
@@ -25,7 +25,6 @@ import org.reactivestreams.Publisher;
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
-import org.springframework.cloud.function.context.FunctionCatalog;
 import org.springframework.cloud.function.context.catalog.FunctionInspector;
 import org.springframework.cloud.function.core.FluxSupplier;
 import org.springframework.cloud.stream.converter.CompositeMessageConverterFactory;
@@ -39,12 +38,13 @@ import org.springframework.util.StringUtils;
 /**
  *
  * @author Oleg Zhurakousky
+ * @author David Turanski
  *
  * @since 2.1
  */
 public class IntegrationFlowFunctionSupport {
 
-	private final FunctionCatalog functionCatalog;
+	private final FunctionCatalogWrapper functionCatalog;
 
 	private final FunctionInspector functionInspector;
 
@@ -58,7 +58,7 @@ public class IntegrationFlowFunctionSupport {
 	 * @param messageConverterFactory
 	 * @param functionProperties
 	 */
-	public IntegrationFlowFunctionSupport(FunctionCatalog functionCatalog, FunctionInspector functionInspector,
+	public IntegrationFlowFunctionSupport(FunctionCatalogWrapper functionCatalog, FunctionInspector functionInspector,
 			CompositeMessageConverterFactory messageConverterFactory, FunctionProperties functionProperties) {
 
 		Assert.notNull(functionCatalog, "'functionCatalog' must not be null");
diff --git a/spring-cloud-stream/src/test/java/org/springframework/cloud/stream/function/SourceToFunctionsSupportTests.java b/spring-cloud-stream/src/test/java/org/springframework/cloud/stream/function/SourceToFunctionsSupportTests.java
index 854d0c24a..919c9faae 100644
--- a/spring-cloud-stream/src/test/java/org/springframework/cloud/stream/function/SourceToFunctionsSupportTests.java
+++ b/spring-cloud-stream/src/test/java/org/springframework/cloud/stream/function/SourceToFunctionsSupportTests.java
@@ -21,10 +21,13 @@ import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Function;
 import java.util.function.Supplier;
 
+import org.junit.Rule;
 import org.junit.Test;
-
+import org.junit.rules.ExpectedException;
 import reactor.core.publisher.Flux;
 
+import org.springframework.beans.BeanInstantiationException;
+import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.WebApplicationType;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
@@ -45,23 +48,27 @@ import org.springframework.util.Assert;
 import org.springframework.util.MimeTypeUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.hamcrest.CoreMatchers.allOf;
+import static org.hamcrest.CoreMatchers.endsWith;
+import static org.hamcrest.CoreMatchers.isA;
+import static org.hamcrest.Matchers.hasProperty;
 
 /**
- *
  * @author Oleg Zhurakousky
- *
+ * @author David Turanski
  * @since 2.1
- *
  */
 public class SourceToFunctionsSupportTests {
 
+	@Rule
+	public ExpectedException expectedException = ExpectedException.none();
+
 	@Test
 	public void testFunctionIsAppliedToExistingMessageSource() {
-		try (ConfigurableApplicationContext context =
-				new SpringApplicationBuilder(
-						TestChannelBinderConfiguration.getCompleteConfiguration(FunctionsConfiguration.class))
-						.web(WebApplicationType.NONE)
-						.run("--spring.cloud.stream.function.name=toUpperCase", "--spring.jmx.enabled=false")) {
+		try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
+			TestChannelBinderConfiguration.getCompleteConfiguration(FunctionsConfiguration.class)).web(
+			WebApplicationType.NONE)
+			.run("--spring.cloud.stream.function.name=toUpperCase", "--spring.jmx.enabled=false")) {
 
 			OutputDestination target = context.getBean(OutputDestination.class);
 			assertThat(target.receive(1000).getPayload()).isEqualTo("HELLO FUNCTION".getBytes(StandardCharsets.UTF_8));
@@ -70,78 +77,75 @@ public class SourceToFunctionsSupportTests {
 
 	@Test
 	public void testComposedFunctionIsAppliedToExistingMessageSource() {
-		try (ConfigurableApplicationContext context =
-				new SpringApplicationBuilder(
-						TestChannelBinderConfiguration.getCompleteConfiguration(FunctionsConfiguration.class))
-						.web(WebApplicationType.NONE)
-						.run("--spring.cloud.stream.function.name=toUpperCase|concatWithSelf",
-								"--spring.jmx.enabled=false")) {
+		try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
+			TestChannelBinderConfiguration.getCompleteConfiguration(FunctionsConfiguration.class)).web(
+			WebApplicationType.NONE)
+			.run("--spring.cloud.stream.function.name=toUpperCase|concatWithSelf", "--spring.jmx.enabled=false")) {
 			OutputDestination target = context.getBean(OutputDestination.class);
-			assertThat(target.receive(1000).getPayload())
-					.isEqualTo("HELLO FUNCTION:HELLO FUNCTION".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(1000).getPayload()).isEqualTo(
+				"HELLO FUNCTION:HELLO FUNCTION".getBytes(StandardCharsets.UTF_8));
 		}
 	}
 
 	@Test
 	public void testMessageSourceIsCreatedFromProvidedSupplier() {
-		try (ConfigurableApplicationContext context =
-				new SpringApplicationBuilder(
-						TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class))
-						.web(WebApplicationType.NONE)
-						.run("--spring.cloud.stream.function.name=number",
-								"--spring.jmx.enabled=false")) {
+		try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
+			TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class)).web(
+			WebApplicationType.NONE).run("--spring.cloud.stream.function.name=number", "--spring.jmx.enabled=false")) {
 
 			OutputDestination target = context.getBean(OutputDestination.class);
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("1".getBytes(StandardCharsets.UTF_8));
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("2".getBytes(StandardCharsets.UTF_8));
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("3".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("1".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("2".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("3".getBytes(StandardCharsets.UTF_8));
 			//etc
 		}
 	}
 
 	@Test
 	public void testMessageSourceIsCreatedFromProvidedSupplierComposedWithSingleFunction() {
-		try (ConfigurableApplicationContext context =
-				new SpringApplicationBuilder(
-						TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class))
-						.web(WebApplicationType.NONE)
-						.run("--spring.cloud.stream.function.name=number|concatWithSelf",
-								"--spring.jmx.enabled=false")) {
+		try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
+			TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class)).web(
+			WebApplicationType.NONE)
+			.run("--spring.cloud.stream.function.name=number|concatWithSelf", "--spring.jmx.enabled=false")) {
 
 			OutputDestination target = context.getBean(OutputDestination.class);
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("11".getBytes(StandardCharsets.UTF_8));
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("22".getBytes(StandardCharsets.UTF_8));
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("33".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("11".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("22".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("33".getBytes(StandardCharsets.UTF_8));
 			//etc
 		}
 	}
 
 	@Test
 	public void testMessageSourceIsCreatedFromProvidedSupplierComposedWithMultipleFunctions() {
-		try (ConfigurableApplicationContext context =
-				new SpringApplicationBuilder(
-						TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class))
-						.web(WebApplicationType.NONE)
-						.run("--spring.cloud.stream.function.name=number|concatWithSelf|multiplyByTwo",
-								"--spring.jmx.enabled=false")) {
+		try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
+			TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class)).web(
+			WebApplicationType.NONE)
+			.run("--spring.cloud.stream.function.name=number|concatWithSelf|multiplyByTwo",
+				"--spring.jmx.enabled=false")) {
 
 			OutputDestination target = context.getBean(OutputDestination.class);
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("22".getBytes(StandardCharsets.UTF_8));
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("44".getBytes(StandardCharsets.UTF_8));
-			assertThat(target.receive(10000).getPayload())
-					.isEqualTo("66".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("22".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("44".getBytes(StandardCharsets.UTF_8));
+			assertThat(target.receive(10000).getPayload()).isEqualTo("66".getBytes(StandardCharsets.UTF_8));
 			//etc
 		}
 	}
 
+	@Test
+	public void testFunctionDoesNotExist() {
+
+		expectedException.expect(BeanCreationException.class);
+		expectedException.expectCause(
+			allOf(isA(BeanInstantiationException.class), hasProperty("cause", isA(IllegalArgumentException.class)),
+				hasProperty("message", endsWith("'doesNotExist' cannot be located."))));
+
+		ConfigurableApplicationContext context = new SpringApplicationBuilder(
+			TestChannelBinderConfiguration.getCompleteConfiguration(SupplierConfiguration.class)).web(
+			WebApplicationType.NONE)
+			.run("--spring.cloud.stream.function.name=doesNotExist", "--spring.jmx.enabled=false");
+	}
+
 	@EnableAutoConfiguration
 	@Import(ProvidedMessageSourceConfiguration.class)
 	public static class SupplierConfiguration {
@@ -195,7 +199,8 @@ public class SourceToFunctionsSupportTests {
 		@Bean
 		public IntegrationFlow messageSourceFlow(IntegrationFlowFunctionSupport functionSupport) {
 			Supplier<Message<String>> messageSource = () -> MessageBuilder.withPayload("hello function")
-					.setHeader(MessageHeaders.CONTENT_TYPE, MimeTypeUtils.TEXT_PLAIN).build();
+				.setHeader(MessageHeaders.CONTENT_TYPE, MimeTypeUtils.TEXT_PLAIN)
+				.build();
 
 			IntegrationFlowBuilder flowBuilder = functionSupport.integrationFlowFromProvidedSupplier(messageSource);
 
@@ -221,10 +226,7 @@ public class SourceToFunctionsSupportTests {
 		public IntegrationFlow messageSourceFlow(IntegrationFlowFunctionSupport functionSupport) {
 			Assert.hasText(this.functionProperties.getName(), "Supplier name must be provided");
 
-			return functionSupport
-					.integrationFlowFromNamedSupplier()
-					.channel(this.source.output())
-					.get();
+			return functionSupport.integrationFlowFromNamedSupplier().channel(this.source.output()).get();
 		}
 
 	}