We have developed a natural language computer program that teaches a clinical approach to disorders of blood coagulation. The purpose of the program was fourfold: to teach a specific set of facts that we considered important to an understanding of hemostasis, to simulate an actual clinical setting in which the student determines the order and content of his patient evaluation; to be adaptive to a student’s responses; and to provide for ready retrieval of student responses. The program is now constructed in two sections. The first section comprises general purpose instructions to the computer that analyze and store input and display the next portion of the lesson according to rules that are independent of the text. The second element consists of specific teaching context. This format allows ready adaptation of the program to teaching other areas of hematology. Experience with the system demonstrates that new subject matter can be easily programmed and revised, that second-year medical students like the approach, and that the subject matter can be effectively taught.