To determine whether admission interviews could differentiate commitment, 456 applicants from 2 medical schools were tested on the commitment, 456 applicants from two medical schools were tested on the Defining Issues Test, which measures the amount of principled or postconventional moral reasoning. The participating institutions were two Israeli institutions: the Sackler School of Medicine, Tel Aviv University, and the Ben-Gurion University. In the Defining Issues Test, the subjects are required to respond to a number of moral dilemmas, each followed by 12 moral issues relating to it. The issues are criteria for solving the dilemma and are designed to represent the various stages of moral development, according to Kohlberg's theory. Each subject rates all the issues in terms of their importance in solving the dilemma, and rank orders the four most important ones. No difference was found between the scores of the accepted and the rejected applicants of the school using traditional scholastic admission criteria. On the other hand, a great difference was shown in the school that admits students for their personal characteristics as assessed by interviews. However, only moderate correlation was found between the test and interview scores. It is suggested that moral reasoning is a key concept in medical professional behavior and is correlated with clinical performance. A possible use of the Defining Issues Test in the student selection process is to increase the predictive value of the admission process while decreasing its cost. Possible explanations for the difference in the response rate between admitted and rejected applicants in both institutions are offered. (SW)