The advent of cheap and powerful micros has opened the possibility of computer-assisted learning (CAL) in medical education. This article attempts to demonstrate the educational value of CAL, with illustrations of its use. Four styles of CAL are examined, and the danger of trivializing the learning process discussed. The ultimate CAL package which enables students to take charge of their own learning is considered. There are considerable advantages in distance learning, self-assessment, computer-marked examinations and 'audit'. Some of the main problems are considered; these are decisions which must be taken about the choice of hardware and software. The use of various peripheral devices such as slide projectors and videodisc players greatly enhances the value of CAL material, as do alternative input devices. Some thought is given to software style in the presentation of material, and also to the question of the keeping of student records. The use of an author language facilitates program development, and the construction of content-free 'shell' programs enables new material to be added to existing frameworks. Other advantages of CAL include student access to JANET and the possibility of on-line searching of databases. CAL in medical education can help to liberate students from the burden of the rote learning of facts, and enhance the role of reason and imagination in the learning process.