International tax law refers to those sections of the U.S. internal revenue code that impose tax on either a) foreign persons or companies that have some commercial contact with the United States or b) U.S. persons who have some commercial contact with another country.
As to foreign clients, for example, that contact may be as slight as a client who merely owns shares in a publicly traded company to as complicated as a major foreign corporation that wishes to create a U.S. or a foreign presence.
As to domestic clients, the issues run anywhere from a U.S. employee becoming a resident of a foreign country to a domestic corporation that wishes to acquire a foreign corporation or partnership.
Those extremes, and everything in between, are what Mr. Rhoades deals with on a daily basis.