To determine whether control of work hours (controllable lifestyle) was becoming an increasingly important factor in choices of specialties by medical students, data from three medical schools over the past ten, ten, and six years, respectively, were reviewed for the types of specialty training entered by students in the top 15% of their classes. Since students in the upper 15% of the class are likely to obtain the specialties of their choice, any change in the pattern of their specialty preferences probably reflects a general trend. Specialties that feature a controllable lifestyle (CL) were defined as anesthesiology, dermatology, emergency medicine, neurology, ophthalmology, otolaryngology, pathology, psychiatry, and radiology. Non-CL specialties were surgery, medicine, family practice, pediatrics, and obstetrics-gynecology. The results showed that the percentages of students entering CL specialties increased significantly at all three schools, the percentages of students entering non-CL specialties decreased significantly at all three schools, and there was no significant change in the percentage of students entering surgical specialties.