diff --git a/camera/aidl/android/hardware/CameraExtensionSessionStats.aidl b/camera/aidl/android/hardware/CameraExtensionSessionStats.aidl
new file mode 100644
index 0000000..1c81831
--- /dev/null
+++ b/camera/aidl/android/hardware/CameraExtensionSessionStats.aidl
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * 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 android.hardware;
+
+/**
+ * Metrics specific to Extension Sessions (see CameraExtensionSession) for logging.
+ *
+ * Each Extension Session is mapped to one camera session internally, and will be sent to
+ * CameraServiceProxy with IDLE/CLOSE calls.
+ * @hide
+ */
+parcelable CameraExtensionSessionStats {
+    /**
+     * Value should match {@code CameraExtensionCharacteristics#EXTENSION_*}
+     */
+    @Backing(type="int")
+    enum Type {
+        EXTENSION_NONE = -1,
+        EXTENSION_AUTOMATIC = 0,
+        EXTENSION_FACE_RETOUCH = 1,
+        EXTENSION_BOKEH = 2,
+        EXTENSION_HDR = 3,
+        EXTENSION_NIGHT = 4
+    }
+
+    /**
+     * Key to uniquely identify the session this stat is associated with. The first call to
+     * 'ICameraService.reportExtensionSessionStats' should set this to an empty string.
+     * 'ICameraService.reportExtensionSessionStats' will return the key which should be used with
+     * the next calls.
+     */
+    String key;
+
+    /**
+     * Camera ID for which the stats is being reported.
+     */
+    String cameraId;
+
+    /**
+     * Package name of the client using the camera
+     */
+    String clientName;
+
+
+    /**
+     * Type of extension session requested by the app. Note that EXTENSION_AUTOMATIC is reported
+     * as such.
+     */
+    Type type = Type.EXTENSION_NONE;
+
+    /**
+     * true if advanced extensions are being used, false otherwise
+     */
+    boolean isAdvanced = false;
+}
\ No newline at end of file
diff --git a/camera/aidl/android/hardware/ICameraService.aidl b/camera/aidl/android/hardware/ICameraService.aidl
index 9f32595..f8e1631 100644
--- a/camera/aidl/android/hardware/ICameraService.aidl
+++ b/camera/aidl/android/hardware/ICameraService.aidl
@@ -30,6 +30,7 @@
 import android.hardware.ICameraServiceListener;
 import android.hardware.CameraInfo;
 import android.hardware.CameraStatus;
+import android.hardware.CameraExtensionSessionStats;
 
 /**
  * Binder interface for the native camera service running in mediaserver.
@@ -214,6 +215,26 @@
      */
     oneway void notifyDeviceStateChange(long newState);
 
+    /**
+     * Report Extension specific metrics to camera service for logging. This should only be called
+     * by CameraExtensionSession to log extension metrics. All calls after the first must set
+     * CameraExtensionSessionStats.key to the value returned by this function.
+     *
+     * Each subsequent call fully overwrites the existing CameraExtensionSessionStats for the
+     * current session, so the caller is responsible for keeping the stats complete.
+     *
+     * Due to cameraservice and cameraservice_proxy architecture, there is no guarantee that
+     * {@code stats} will be logged immediately (or at all). CameraService will log whatever
+     * extension stats it has at the time of camera session closing which may be before the app
+     * process receives a session/device closed callback; so CameraExtensionSession
+     * should send metrics to the cameraservice preriodically, and cameraservice must handle calls
+     * to this function from sessions that have not been logged yet and from sessions that have
+     * already been closed.
+     *
+     * @return the key that must be used to report updates to previously reported stats.
+     */
+    String reportExtensionSessionStats(in CameraExtensionSessionStats stats);
+
     // Bitfield constants for notifyDeviceStateChange
     // All bits >= 32 are for custom vendor states
     // Written as ints since AIDL does not support long constants.
diff --git a/camera/aidl/android/hardware/ICameraServiceProxy.aidl b/camera/aidl/android/hardware/ICameraServiceProxy.aidl
index be8a00f..4faa6b4 100644
--- a/camera/aidl/android/hardware/ICameraServiceProxy.aidl
+++ b/camera/aidl/android/hardware/ICameraServiceProxy.aidl
@@ -17,6 +17,7 @@
 package android.hardware;
 
 import android.hardware.CameraSessionStats;
+import android.hardware.CameraExtensionSessionStats;
 
 /**
  * Binder interface for the camera service proxy running in system_server.