The NORAD commander-in-chief is always a United States Department of Defense four-star General or equivalent confirmed by the US Senate and is also in command of USNORTHCOM, while the Deputy Commander is always Canadian. Since 2004 commanders have included Admirals.
Deputy commanders
In recent years deputy commanders have always been Canadian air force lieutenant generals. Prior to the 1968 unification of the Canadian Forces, the deputy commanders were RCAF Air Marshals.
References
Commander-in-Chief of the North American Aerospace Defense Command Wikipedia(Text) CC BY-SA