Yes, Arizona does restrict who can practice engineering! from http://www.azleg.state.az.us/FormatDocument.asp?inDoc=/ars/32/00123.htm&Title=32&DocType=ARS Arizona Revised Statues 32-123. Application for registration and certification (L00, ch 86, sec. 7) A. A person desiring to practice architecture, assaying, engineering, geology, home inspection, landscape architecture or land surveying shall make application for registration or certification on a form prescribed by the board, subscribed under oath and accompanied by the application fee. If the evidence submitted satisfies the board that the applicant is fully qualified, under section 32-122.01, 32-122.02 or 32-126, to practice the profession for which registration or certification is asked, it shall give the applicant a certificate of registration or certification, signed by the chairman and secretary and attested by the official seal. If the applicant seeks registration as a professional engineer, the certificate of registration shall list the proficiency designation in the branch of engineering in which the applicant has demonstrated proficiency.