The growing enrollment of foreign graduate students at American colleges, particularly in the sciences, has alarmed many politicians and educators. Some fear that the United States is, in effect, subsidizing the training of its economic competitors. Others worry that too little is being done to encourage more Americans to obtain a graduate education in technical and scientific fields. Some universities are taking steps to admit more Americans. The University of Tennessee at Knoxville is thought to be the only institution with explicit limits on the enrollment of foreign graduate students. At Knoxville, no more than 20 per cent of graduate enrollment can be made up of international students. And no more than 75 students may enroll from any one country. Supporters of the policy say the rules force the university to focus on training Americans. Critics say the university has been forced to admit mediocre Americans to some of its programs. Should universities be worried about foreign enrollments? Should colleges in the United States adopt policies to insure that more of their graduate students in the sciences are Americans? Should universities set quotas on foreign students? What steps could American institutions take to increase the interest of U.S. citizens in science?