diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/SpanExtractor.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/SpanExtractor.java
new file mode 100644
index 000000000..eb41899f1
--- /dev/null
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/SpanExtractor.java
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2015 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.sleuth.instrument;
+
+import org.springframework.cloud.sleuth.Span;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public interface SpanExtractor<T, U> {
+
+	Span extract(T input, TraceKeys keys);
+
+	void inject(Span span, U output, TraceKeys keys);
+
+}
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/LazyTraceExecutor.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/LazyTraceExecutor.java
index 6f894d210..dea70c531 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/LazyTraceExecutor.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/LazyTraceExecutor.java
@@ -21,7 +21,6 @@ import java.util.concurrent.Executor;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.cloud.sleuth.Tracer;
-import org.springframework.cloud.sleuth.instrument.TraceRunnable;
 
 import lombok.RequiredArgsConstructor;
 
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceCallable.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceCallable.java
similarity index 95%
rename from spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceCallable.java
rename to spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceCallable.java
index 90e27405a..6ec4e250b 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceCallable.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceCallable.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.cloud.sleuth.instrument;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import java.util.concurrent.Callable;
 
@@ -31,7 +31,6 @@ import lombok.Value;
 @EqualsAndHashCode(callSuper = false)
 public class TraceCallable<V> extends TraceDelegate<Callable<V>> implements Callable<V> {
 
-
 	public TraceCallable(Tracer tracer, Callable<V> delegate) {
 		super(tracer, delegate);
 	}
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceDelegate.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceDelegate.java
similarity index 96%
rename from spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceDelegate.java
rename to spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceDelegate.java
index 2a38f52ee..07c40c03e 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceDelegate.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceDelegate.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.cloud.sleuth.instrument;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import org.springframework.cloud.sleuth.Span;
 import org.springframework.cloud.sleuth.Tracer;
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceRunnable.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceRunnable.java
similarity index 95%
rename from spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceRunnable.java
rename to spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceRunnable.java
index 08f384b3f..80ae3b1dc 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/TraceRunnable.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceRunnable.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.cloud.sleuth.instrument;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import org.springframework.cloud.sleuth.Span;
 import org.springframework.cloud.sleuth.Tracer;
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/executor/TraceableExecutorService.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceableExecutorService.java
similarity index 91%
rename from spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/executor/TraceableExecutorService.java
rename to spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceableExecutorService.java
index 0c9bc5a0e..d502747ed 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/executor/TraceableExecutorService.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceableExecutorService.java
@@ -13,7 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.springframework.cloud.sleuth.instrument.executor;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import java.util.Collection;
 import java.util.List;
@@ -25,8 +25,6 @@ import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 
 import org.springframework.cloud.sleuth.Tracer;
-import org.springframework.cloud.sleuth.instrument.TraceCallable;
-import org.springframework.cloud.sleuth.instrument.TraceRunnable;
 /**
  * A decorator class for {@link ExecutorService} to support tracing in Executors
  * @author Gaurav Rai Mazra
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/executor/TraceableScheduledExecutorService.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceableScheduledExecutorService.java
similarity index 89%
rename from spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/executor/TraceableScheduledExecutorService.java
rename to spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceableScheduledExecutorService.java
index 5facfb2e1..5e271ebce 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/executor/TraceableScheduledExecutorService.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/async/TraceableScheduledExecutorService.java
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.cloud.sleuth.instrument.executor;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import java.util.concurrent.Callable;
 import java.util.concurrent.ScheduledExecutorService;
@@ -22,8 +22,6 @@ import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
 
 import org.springframework.cloud.sleuth.Tracer;
-import org.springframework.cloud.sleuth.instrument.TraceCallable;
-import org.springframework.cloud.sleuth.instrument.TraceRunnable;
 
 /**
  * A decorator class for {@link ScheduledExecutorService} to support tracing in Executors
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceWebAspect.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceWebAspect.java
index 0b6676b07..83e171020 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceWebAspect.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/instrument/web/TraceWebAspect.java
@@ -23,7 +23,7 @@ import org.aspectj.lang.annotation.Aspect;
 import org.aspectj.lang.annotation.Pointcut;
 import org.springframework.cloud.sleuth.SpanAccessor;
 import org.springframework.cloud.sleuth.Tracer;
-import org.springframework.cloud.sleuth.instrument.TraceCallable;
+import org.springframework.cloud.sleuth.instrument.async.TraceCallable;
 import org.springframework.web.context.request.async.WebAsyncTask;
 
 import java.lang.reflect.Field;
diff --git a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/trace/DefaultTracer.java b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/trace/DefaultTracer.java
index 88c0b65b1..399e9303f 100644
--- a/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/trace/DefaultTracer.java
+++ b/spring-cloud-sleuth-core/src/main/java/org/springframework/cloud/sleuth/trace/DefaultTracer.java
@@ -25,8 +25,8 @@ import org.springframework.cloud.sleuth.Tracer;
 import org.springframework.cloud.sleuth.event.SpanAcquiredEvent;
 import org.springframework.cloud.sleuth.event.SpanContinuedEvent;
 import org.springframework.cloud.sleuth.event.SpanReleasedEvent;
-import org.springframework.cloud.sleuth.instrument.TraceCallable;
-import org.springframework.cloud.sleuth.instrument.TraceRunnable;
+import org.springframework.cloud.sleuth.instrument.async.TraceCallable;
+import org.springframework.cloud.sleuth.instrument.async.TraceRunnable;
 import org.springframework.cloud.sleuth.util.ExceptionUtils;
 import org.springframework.context.ApplicationEventPublisher;
 
diff --git a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/TraceCallableTests.java b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceCallableTests.java
similarity index 95%
rename from spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/TraceCallableTests.java
rename to spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceCallableTests.java
index 9f468ec83..53012a6fe 100644
--- a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/TraceCallableTests.java
+++ b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceCallableTests.java
@@ -1,4 +1,4 @@
-package org.springframework.cloud.sleuth.instrument;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import org.junit.After;
 import org.junit.Test;
@@ -7,6 +7,7 @@ import org.mockito.Mockito;
 import org.mockito.runners.MockitoJUnitRunner;
 import org.springframework.cloud.sleuth.Span;
 import org.springframework.cloud.sleuth.Tracer;
+import org.springframework.cloud.sleuth.instrument.async.TraceCallable;
 import org.springframework.cloud.sleuth.sampler.AlwaysSampler;
 import org.springframework.cloud.sleuth.trace.DefaultTracer;
 import org.springframework.cloud.sleuth.trace.TestSpanContextHolder;
diff --git a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/TraceRunnableTests.java b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceRunnableTests.java
similarity index 95%
rename from spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/TraceRunnableTests.java
rename to spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceRunnableTests.java
index be70f35de..9b4b21514 100644
--- a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/TraceRunnableTests.java
+++ b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceRunnableTests.java
@@ -1,4 +1,4 @@
-package org.springframework.cloud.sleuth.instrument;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import org.junit.After;
 import org.junit.Test;
@@ -7,6 +7,7 @@ import org.mockito.Mockito;
 import org.mockito.runners.MockitoJUnitRunner;
 import org.springframework.cloud.sleuth.Span;
 import org.springframework.cloud.sleuth.Tracer;
+import org.springframework.cloud.sleuth.instrument.async.TraceRunnable;
 import org.springframework.cloud.sleuth.sampler.AlwaysSampler;
 import org.springframework.cloud.sleuth.trace.DefaultTracer;
 import org.springframework.cloud.sleuth.trace.TestSpanContextHolder;
diff --git a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/executor/TraceableExecutorServiceTests.java b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceableExecutorServiceTests.java
similarity index 95%
rename from spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/executor/TraceableExecutorServiceTests.java
rename to spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceableExecutorServiceTests.java
index 406f7c895..9550cab6e 100644
--- a/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/executor/TraceableExecutorServiceTests.java
+++ b/spring-cloud-sleuth-core/src/test/java/org/springframework/cloud/sleuth/instrument/async/TraceableExecutorServiceTests.java
@@ -1,4 +1,4 @@
-package org.springframework.cloud.sleuth.instrument.executor;
+package org.springframework.cloud.sleuth.instrument.async;
 
 import lombok.SneakyThrows;
 import org.junit.After;
@@ -9,6 +9,7 @@ import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
 import org.springframework.cloud.sleuth.Span;
 import org.springframework.cloud.sleuth.Tracer;
+import org.springframework.cloud.sleuth.instrument.async.TraceableExecutorService;
 import org.springframework.cloud.sleuth.sampler.AlwaysSampler;
 import org.springframework.cloud.sleuth.trace.DefaultTracer;
 import org.springframework.cloud.sleuth.trace.TestSpanContextHolder;