The concept of integration of the medical curriculum is analysed in terms of three principles: (i) the philosophical principle of the unified universe; (ii) the theory of the structure of knowledge; and (iii) development creative thinking through 'pattern' formation and flow of relevant associations. The proposal is discussed to describe and classify methods of integration in six parameters: 1. scope of material integrated; 2. time of commencement; 3. teaching-learning environment; 4. mental processes involved; 5. the student's role; and 6. direction. A description of integrating methods follows, all simultaneously used in the Faculty of Health Science, Ben-Gurion University of Negev. The conclusion is that there is no 'right' and 'wrong' way to integrate subject matter; each medical school may select a method appropriate for its goals, structure and constraints.