A repeated measures design was used to trace 83 baccalaureate students' critical thinking (CT) ability as they progressed in a nursing program. CT was assessed with the Watson-Glaser Critical Thinking Appraisal at four strategic junctures in the curriculum; program entry, mid junior year, beginning of senior year, and program exit. Sixty students (Group One) had been in the program when the study began and were not pretested. Group Two (N = 23) was tested at all four junctures. The sample was racially and culturally diverse, predominantly female, and a majority had prior college. Over time, scores tended not to improve, and they were below published norms. Findings are discussed from the perspectives of what constitutes CT in nursing and its measurement, the cultural context of its assessment, and the nature of nursing education and its influence on CT.