We incorporated clay modeling into gross anatomy and neuro-anatomy courses to help students understand cross-sectional anatomy. By making clay models, cutting them and comparing cut surfaces to CT and MR images, students learned how cross-sectional two-dimensional images were created from three-dimensional structure of human organs. Most students in a clay modeling group responded positively to this approach, and their average score on CT examination was higher than that of a group that did not use clay models. Clay modeling appears to be a useful supplement to conventional anatomy or radiologic anatomy education. It can be applied to any part of human body, and its effectiveness will be greater when a more complicated understanding of cross-sectional anatomy is required. (Contains 1 table and 4 figures.)