The study examined the differences between international and U.S. citizen faculty members' productivity in the areas of research, graduate and undergraduate teaching, and service at research universities in the United States. Utilizing the 2004 National Study of Postsecondary Faculty (NSOPF:04) data set, we used a Structural Equation Modeling (SEM) to address the primary research questions in the study. The results indicated that international faculty members were significantly more productive in research, but less productive in teaching and service than their U.S. citizen colleagues. The study can potentially aid policymakers and university administrators to not only better serve and support international faculty members but also to fully utilize them as a resource that benefits the institution and the students in all functions of their work and not just in research.