The ability of students in a dietitian program to assess their own performance improved dramatically with time during a 16-week period, using the critical incident technique as a basis for evaluation. Summary records of performance in various activity categories were evaluated three times during the semester by instructors and students, and the degree of agreement was compared. The percentages of agreement increased steadily from the first to third evaluation period: 75.6% at first, 88.4% in the second period, and 90.0% in the third period. The greatest proportional gains by students were in the categories of "acceptance of professional responsibility" and "judgment regarding professional values." The self-assessment feature is an important part of instruction and helpful in developing competency