diff --git a/neuralnetworks/1.0/IDevice.hal b/neuralnetworks/1.0/IDevice.hal
index b826b23..9e19097 100644
--- a/neuralnetworks/1.0/IDevice.hal
+++ b/neuralnetworks/1.0/IDevice.hal
@@ -18,6 +18,7 @@
 
 package android.hardware.neuralnetworks@1.0;
 
+import IEvent;
 import IPreparedModel;
 
 interface IDevice {
@@ -25,7 +26,7 @@
 
     getSupportedSubgraph(Model model) generates(vec<bool> supported);
 
-    prepareModel(Model model) generates(IPreparedModel preparedModel);
+    prepareModel(Model model, IEvent event) generates(IPreparedModel preparedModel);
 
     getStatus() generates(DeviceStatus status);
 };
diff --git a/neuralnetworks/1.0/vts/functional/VtsHalNeuralnetworksV1_0TargetTest.cpp b/neuralnetworks/1.0/vts/functional/VtsHalNeuralnetworksV1_0TargetTest.cpp
index 90ccd06..9c64c04 100644
--- a/neuralnetworks/1.0/vts/functional/VtsHalNeuralnetworksV1_0TargetTest.cpp
+++ b/neuralnetworks/1.0/vts/functional/VtsHalNeuralnetworksV1_0TargetTest.cpp
@@ -209,10 +209,14 @@
     const uint32_t INPUT = 0;
     const uint32_t OUTPUT = 1;
 
-    // prpeare request
+    // prepare request
     Model model = createTestModel();
-    sp<IPreparedModel> preparedModel = device->prepareModel(model);
+    sp<Event> preparationEvent = new Event();
+    ASSERT_NE(nullptr, preparationEvent.get());
+    sp<IPreparedModel> preparedModel = device->prepareModel(model, preparationEvent);
     ASSERT_NE(nullptr, preparedModel.get());
+    Event::Status preparationStatus = preparationEvent->wait();
+    EXPECT_EQ(Event::Status::SUCCESS, preparationStatus);
 
     // prepare inputs
     uint32_t inputSize = static_cast<uint32_t>(inputData.size() * sizeof(float));
@@ -245,13 +249,13 @@
     outputMemory->commit();
 
     // execute request
-    sp<Event> event = sp<Event>(new Event());
-    ASSERT_NE(nullptr, event.get());
+    sp<Event> executionEvent = new Event();
+    ASSERT_NE(nullptr, executionEvent.get());
     bool success = preparedModel->execute({.inputs = inputs, .outputs = outputs, .pools = pools},
-                                          event);
+                                          executionEvent);
     EXPECT_TRUE(success);
-    Event::Status status = event->wait();
-    EXPECT_EQ(Event::Status::SUCCESS, status);
+    Event::Status executionStatus = executionEvent->wait();
+    EXPECT_EQ(Event::Status::SUCCESS, executionStatus);
 
     // validate results { 1+5, 2+6, 3+7, 4+8 }
     outputMemory->read();