diff --git a/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/AccountController.java b/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/AccountController.java
index 764b28f..49ce442 100644
--- a/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/AccountController.java
+++ b/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/AccountController.java
@@ -10,6 +10,8 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.context.request.async.DeferredResult;
+
+import rx.Observable;
 import rx.functions.Func1;
 
 @RestController
@@ -24,14 +26,14 @@ public class AccountController {
   }
 
   @RequestMapping(method = RequestMethod.POST)
-  public DeferredResult<CreateAccountResponse> createAccount(@RequestBody CreateAccountRequest request) {
-    return DeferredUtils.toDeferredResult(accountService.openAccount(request.getInitialBalance()).map(new Func1<EntityWithIdAndVersion<Account>, CreateAccountResponse>() {
+  public Observable<CreateAccountResponse> createAccount(@RequestBody CreateAccountRequest request) {
+    return accountService.openAccount(request.getInitialBalance()).map(new Func1<EntityWithIdAndVersion<Account>, CreateAccountResponse>() {
 
       @Override
       public CreateAccountResponse call(EntityWithIdAndVersion<Account> entityAndEventInfo) {
         return new CreateAccountResponse(entityAndEventInfo.getEntityIdentifier().getId());
       }
 
-    }));
+    });
   }
 }
diff --git a/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/CommandSideWebAccountsConfiguration.java b/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/CommandSideWebAccountsConfiguration.java
index e9caf42..06b56c7 100644
--- a/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/CommandSideWebAccountsConfiguration.java
+++ b/java-spring/accounts-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/accounts/CommandSideWebAccountsConfiguration.java
@@ -1,13 +1,24 @@
 package net.chrisrichardson.eventstore.javaexamples.banking.web.commandside.accounts;
 
+import java.util.List;
+
 import net.chrisrichardson.eventstore.javaexamples.banking.backend.commandside.accounts.AccountConfiguration;
+import net.chrisrichardson.eventstore.javaexamples.banking.web.util.ObservableReturnValueHandler;
+
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
+import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
 
 @Configuration
 @Import({AccountConfiguration.class})
 @ComponentScan
-public class CommandSideWebAccountsConfiguration {
+public class CommandSideWebAccountsConfiguration extends WebMvcConfigurerAdapter {
+
+	@Override
+	public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> handlers) {
+		handlers.add(new ObservableReturnValueHandler());
+	}
 
 }
diff --git a/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/QuerySideWebConfiguration.java b/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/QuerySideWebConfiguration.java
index a55d90a..d8f5ede 100644
--- a/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/QuerySideWebConfiguration.java
+++ b/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/QuerySideWebConfiguration.java
@@ -1,12 +1,24 @@
 package net.chrisrichardson.eventstore.javaexamples.banking.web.queryside;
 
+import java.util.List;
+
 import net.chrisrichardson.eventstore.javaexamples.banking.backend.queryside.accounts.QuerySideAccountConfiguration;
+import net.chrisrichardson.eventstore.javaexamples.banking.web.util.ObservableReturnValueHandler;
+
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
+import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
 
 @Configuration
 @Import({QuerySideAccountConfiguration.class})
 @ComponentScan
-public class QuerySideWebConfiguration {
+public class QuerySideWebConfiguration extends WebMvcConfigurerAdapter {
+
+	@Override
+	public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> handlers) {
+		handlers.add(new ObservableReturnValueHandler());
+	}
+
 }
diff --git a/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/accounts/AccountQueryController.java b/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/accounts/AccountQueryController.java
index 2cdcbb6..7e554c6 100644
--- a/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/accounts/AccountQueryController.java
+++ b/java-spring/accounts-query-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/queryside/accounts/AccountQueryController.java
@@ -9,6 +9,8 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.context.request.async.DeferredResult;
+
+import rx.Observable;
 import rx.functions.Func1;
 
 import java.math.BigDecimal;
@@ -24,13 +26,13 @@ public class AccountQueryController {
   }
 
   @RequestMapping(value="/accounts/{accountId}", method = RequestMethod.GET)
-  public DeferredResult<GetAccountResponse> get(@PathVariable String accountId) {
-    return DeferredUtils.toDeferredResult(accountInfoQueryService.findByAccountId(new EntityIdentifier(accountId)).map(new Func1<AccountInfo, GetAccountResponse>() {
+  public Observable<GetAccountResponse> get(@PathVariable String accountId) {
+    return accountInfoQueryService.findByAccountId(new EntityIdentifier(accountId)).map(new Func1<AccountInfo, GetAccountResponse>() {
       @Override
       public GetAccountResponse call(AccountInfo accountInfo) {
         return new GetAccountResponse(accountInfo.getId(), new BigDecimal(accountInfo.getBalance()));
       }
-    }));
+    });
   }
 
   @ResponseStatus(value= HttpStatus.NOT_FOUND, reason="account not found")
diff --git a/java-spring/common-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/util/ObservableReturnValueHandler.java b/java-spring/common-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/util/ObservableReturnValueHandler.java
new file mode 100644
index 0000000..207b48a
--- /dev/null
+++ b/java-spring/common-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/util/ObservableReturnValueHandler.java
@@ -0,0 +1,31 @@
+package net.chrisrichardson.eventstore.javaexamples.banking.web.util;
+
+import rx.Observable;
+
+import org.springframework.core.MethodParameter;
+import org.springframework.web.context.request.NativeWebRequest;
+import org.springframework.web.context.request.async.DeferredResult;
+import org.springframework.web.context.request.async.WebAsyncUtils;
+import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
+import org.springframework.web.method.support.ModelAndViewContainer;
+
+
+public class ObservableReturnValueHandler implements HandlerMethodReturnValueHandler {
+
+	@Override
+	public boolean supportsReturnType(MethodParameter returnType) {
+		return Observable.class.equals(returnType.getParameterType());
+	}
+
+	@Override
+	public void handleReturnValue(Object returnValue, MethodParameter returnType, ModelAndViewContainer mavContainer,
+			NativeWebRequest webRequest) throws Exception {
+
+		if (returnValue == null) {
+			return;
+		}
+		DeferredResult<?> d = DeferredUtils.toDeferredResult((Observable<?>) returnValue);
+		WebAsyncUtils.getAsyncManager(webRequest).startDeferredResultProcessing(d);
+	}
+
+}
diff --git a/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/CommandSideWebTransactionsConfiguration.java b/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/CommandSideWebTransactionsConfiguration.java
index e9c9f55..1b29be9 100644
--- a/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/CommandSideWebTransactionsConfiguration.java
+++ b/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/CommandSideWebTransactionsConfiguration.java
@@ -1,13 +1,24 @@
 package net.chrisrichardson.eventstore.javaexamples.banking.web.commandside.transactions;
 
+import java.util.List;
+
 import net.chrisrichardson.eventstore.javaexamples.banking.backend.commandside.transactions.MoneyTransferConfiguration;
+import net.chrisrichardson.eventstore.javaexamples.banking.web.util.ObservableReturnValueHandler;
+
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
+import org.springframework.web.method.support.HandlerMethodReturnValueHandler;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
 
 @Configuration
 @Import({MoneyTransferConfiguration.class})
 @ComponentScan
-public class CommandSideWebTransactionsConfiguration {
+public class CommandSideWebTransactionsConfiguration extends WebMvcConfigurerAdapter {
+
+	@Override
+	public void addReturnValueHandlers(List<HandlerMethodReturnValueHandler> handlers) {
+		handlers.add(new ObservableReturnValueHandler());
+	}
 
 }
diff --git a/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/MoneyTransferController.java b/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/MoneyTransferController.java
index c173e50..f5430b1 100644
--- a/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/MoneyTransferController.java
+++ b/java-spring/transactions-command-side-web/src/main/java/net/chrisrichardson/eventstore/javaexamples/banking/web/commandside/transactions/MoneyTransferController.java
@@ -12,6 +12,8 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.context.request.async.DeferredResult;
+
+import rx.Observable;
 import rx.functions.Func1;
 
 @RestController
@@ -26,16 +28,16 @@ public class MoneyTransferController {
   }
 
   @RequestMapping(method = RequestMethod.POST)
-  public DeferredResult<CreateMoneyTransferResponse> createMoneyTransfer(@RequestBody CreateMoneyTransferRequest request) {
+  public Observable<CreateMoneyTransferResponse> createMoneyTransfer(@RequestBody CreateMoneyTransferRequest request) {
     TransferDetails transferDetails = new TransferDetails(new EntityIdentifier(request.getFromAccountId()), new EntityIdentifier(request.getToAccountId()), request.getAmount());
-    return DeferredUtils.toDeferredResult(moneyTransferService.transferMoney(transferDetails).map(new Func1<EntityWithIdAndVersion<MoneyTransfer>, CreateMoneyTransferResponse>() {
+    return moneyTransferService.transferMoney(transferDetails).map(new Func1<EntityWithIdAndVersion<MoneyTransfer>, CreateMoneyTransferResponse>() {
 
       @Override
       public CreateMoneyTransferResponse call(EntityWithIdAndVersion<MoneyTransfer> entityAndEventInfo) {
         return new CreateMoneyTransferResponse(entityAndEventInfo.getEntityIdentifier().getId());
       }
 
-    }));
+    });
   }
 
 }