The purpose of this study has been to find a basis for the development of guidelines for EFL/ESP courses for university students of science, mathematics and literature. Part I considers the theoretical background to the present EFL/ESP situation. It discusses the various approaches to the teaching of ESP in terms of syllabus content, methodology, the structural, situational, notional approaches and the communicative approach. Part II is concerned with the experimental study. It discusses the results of 'Case Study I - Needs Analysis for Science and Mathematics Students' and 'Case Study II - Needs Analysis for Literature Students'. Part III gives an outline of model EFL/ESP courses, conclusions and related areas requiring further investigation.