diff --git a/src/main/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceController.java b/src/main/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceController.java
index 9421b418..50d98a97 100644
--- a/src/main/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceController.java
+++ b/src/main/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceController.java
@@ -100,8 +100,8 @@ public class ServiceInstanceController extends BaseController {
 	}, method = RequestMethod.GET)
 	public ResponseEntity<?> getServiceInstanceLastOperation(@PathVariable Map<String, String> pathVariables,
 															 @PathVariable("instanceId") String serviceInstanceId,
-															 @RequestParam("service_id") String serviceDefinitionId,
-															 @RequestParam("plan_id") String planId,
+															 @RequestParam(value = "service_id", required = false) String serviceDefinitionId,
+															 @RequestParam(value = "plan_id", required = false) String planId,
 															 @RequestParam(value = "operation", required = false) String operation,
 															 @RequestHeader(value = API_INFO_LOCATION_HEADER, required = false) String apiInfoLocation,
 															 @RequestHeader(value = ORIGINATING_IDENTITY_HEADER, required = false) String originatingIdentityString) {
diff --git a/src/test/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceControllerIntegrationTest.java b/src/test/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceControllerIntegrationTest.java
index 8b7fb8bd..13f79328 100644
--- a/src/test/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceControllerIntegrationTest.java
+++ b/src/test/java/org/springframework/cloud/servicebroker/controller/ServiceInstanceControllerIntegrationTest.java
@@ -73,6 +73,7 @@ public class ServiceInstanceControllerIntegrationTest extends ControllerIntegrat
 	private UpdateServiceInstanceResponse asyncUpdateResponse;
 
 	private GetLastServiceOperationRequest lastOperationRequest;
+	private GetLastServiceOperationRequest lastOperationRequestWithoutOptionalParameters;
 
 	@Before
 	public void setup() {
@@ -99,6 +100,8 @@ public class ServiceInstanceControllerIntegrationTest extends ControllerIntegrat
 		asyncUpdateResponse = ServiceInstanceFixture.buildUpdateServiceInstanceResponse(true);
 
 		lastOperationRequest = ServiceInstanceFixture.buildGetLastOperationRequest();
+		lastOperationRequestWithoutOptionalParameters =
+				ServiceInstanceFixture.buildGetLastOperationRequestWithoutOptionalParameters();
 	}
 
 	@Test
@@ -588,6 +591,22 @@ public class ServiceInstanceControllerIntegrationTest extends ControllerIntegrat
 				.andExpect(jsonPath("$.description", is("all good")));
 	}
 
+	@Test
+	public void lastOperationHasSucceededStatusWithoutOptionalParameters() throws Exception {
+		GetLastServiceOperationResponse response = new GetLastServiceOperationResponse()
+				.withOperationState(OperationState.SUCCEEDED)
+				.withDescription("all good");
+
+		when(serviceInstanceService.getLastOperation(eq(lastOperationRequestWithoutOptionalParameters)))
+				.thenReturn(response);
+
+		mockMvc.perform(get(buildUrl(lastOperationRequestWithoutOptionalParameters, false))
+				.header(API_INFO_LOCATION_HEADER, API_INFO_LOCATION))
+				.andExpect(status().isOk())
+				.andExpect(jsonPath("$.state", is(OperationState.SUCCEEDED.toString())))
+				.andExpect(jsonPath("$.description", is("all good")));
+	}
+
 	@Test
 	public void lastOperationHasSucceededStatusWithCfInstanceId() throws Exception {
 		GetLastServiceOperationResponse response = new GetLastServiceOperationResponse()
diff --git a/src/test/java/org/springframework/cloud/servicebroker/model/fixture/ServiceInstanceFixture.java b/src/test/java/org/springframework/cloud/servicebroker/model/fixture/ServiceInstanceFixture.java
index d985c25b..ea6aa809 100644
--- a/src/test/java/org/springframework/cloud/servicebroker/model/fixture/ServiceInstanceFixture.java
+++ b/src/test/java/org/springframework/cloud/servicebroker/model/fixture/ServiceInstanceFixture.java
@@ -73,4 +73,8 @@ public class ServiceInstanceFixture {
 				service.getPlans().get(0).getId(),
 				"task_10");
 	}
+
+	public static GetLastServiceOperationRequest buildGetLastOperationRequestWithoutOptionalParameters() {
+		return new GetLastServiceOperationRequest("service-instance-id");
+	}
 }