diff --git a/Assets/FirstPersonController/Scripts/MouseLook.cs b/Assets/FirstPersonController/Scripts/MouseLook.cs
index 3e4caf6..a051aca 100644
--- a/Assets/FirstPersonController/Scripts/MouseLook.cs
+++ b/Assets/FirstPersonController/Scripts/MouseLook.cs
@@ -1,37 +1,55 @@
 /******************************************************************************
  * Initial code based on Brackey's FPS video
  * https://youtu.be/_QajrabyTJc
+ * 
+ * Notes:
+ * In the video, he attaches this script to the camera. I refactored it to put
+ * it up on the main player element. That way the behaviors are all in one 
+ * place and "hidden."
+ * 
+ * Changed the mouse sensitivity variable to use a Float Reference. This allows
+ * me to put the value into a property/settings UI so the player can change the
+ * value to his/her preference. Or it can be changed at design time in Unity.
  *****************************************************************************/
 
-using System.Collections;
-using System.Collections.Generic;
+/******************************************************************************
+ * The Mouse Look script is responsible for rotating the player object and the
+ * main camera in response to the movement of the mouse.
+ * 
+ * Movement of the mouse on the Y axis simulates looking up and down. This will
+ * rotate the camera and is clamped to a human-like range of motion.
+ * 
+ * Movement on the mouse on the X axis simulates turning. This will rotate the
+ * player object.
+ *****************************************************************************/
+using Architecture.Variables;
 using UnityEngine;
 
 public class MouseLook : MonoBehaviour
 {
-    public float mouseSensitivity = 100f;
-    public Transform playerBody;
-
+    [SerializeField] private FloatReference mouseSensitivity;
     private float xRotation = 0f;
 
-    // Start is called before the first frame update
+    [SerializeField] private Transform mainCamera;
+
     void Start()
     {
         // Keep the mouse cursor in the game window
         Cursor.lockState = CursorLockMode.Locked;
     }
 
-    // Update is called once per frame
     void Update()
     {
-        float mouseX = Input.GetAxis("Mouse X") * mouseSensitivity * Time.deltaTime;
-        float mouseY = Input.GetAxis("Mouse Y") * mouseSensitivity * Time.deltaTime;
+        float mouseX = Input.GetAxis("Mouse X") * mouseSensitivity.Value * Time.deltaTime;
+        float mouseY = Input.GetAxis("Mouse Y") * mouseSensitivity.Value * Time.deltaTime;
 
+        // Simulate looking up and down by rotating the camera. Clamp the rotation 
+        // to limit the range of motion.
         xRotation -= mouseY;
         xRotation = Mathf.Clamp(xRotation, -90f, 90f);
-        transform.localRotation = Quaternion.Euler(xRotation, 0f, 0f);
-
-        playerBody.Rotate(Vector3.up * mouseX);
+        mainCamera.localRotation = Quaternion.Euler(xRotation, 0f, 0f);
 
+        // Simulate turning
+        transform.Rotate(Vector3.up * mouseX);
     }
 }
diff --git a/Assets/FirstPersonController/Variables.meta b/Assets/FirstPersonController/Variables.meta
new file mode 100644
index 0000000..0081159
--- /dev/null
+++ b/Assets/FirstPersonController/Variables.meta
@@ -0,0 +1,8 @@
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diff --git a/Assets/FirstPersonController/Variables/MouseSensitivity.asset b/Assets/FirstPersonController/Variables/MouseSensitivity.asset
new file mode 100644
index 0000000..dff8dc7
--- /dev/null
+++ b/Assets/FirstPersonController/Variables/MouseSensitivity.asset
@@ -0,0 +1,16 @@
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diff --git a/Assets/FirstPersonController/Variables/MouseSensitivity.asset.meta b/Assets/FirstPersonController/Variables/MouseSensitivity.asset.meta
new file mode 100644
index 0000000..3c33b6e
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