Tax treaties signed between the United States of America and other countries do not define various terms used in the treaties. Absences of such definitions contribute to creating disputes between tax payers and the Internal Revenue Service (IRS). Some of those disputes end up in tax courts. This article critically analyses various income tax exemption benefits available to nonresident alien students, scholars, trainees, and teachers in light of select income tax treaties/conventions. We also evaluate select tax court precedents interpreting various tax treaty benefits and the terms used in these tax treaties as interpreted by the US tax courts.