Certain professionals from Canada or Mexico may enter the United States on a TN visa for temporary employment under the provisions of the North American Free Trade Agreement. The visitor’s spouse and minor children may accompany or follow later as well under the associated TD visa program, though such family members are not permitted to work in the U.S. The TN visa program was designed to facilitate the movement of businesspersons among the U.S., Canada, and Mexico for certain investment, trade, and other commercial services. Thus, applicants must show that they’ll be conducting business in one of the 63 authorized professions under NAFTA, including: accountants, architects, economists, engineers, interior designers, lawyers, librarians, vocational counselors, dentists, pharmacists, nutritionists, veterinarians, meteorologists, zoologists, horticulturalists, and college or university teachers. You can find the complete list of authorized professions at the USCIS website.