Teaching materials and the roles of EFL/ESL teachers is published amidst a decade long increase in academic publications and training courses concerned with the evaluation and design of English language teaching materials. It is timely to consider what effect the advice on offer has had on teachers' practice. Are teachers evaluating materials carefully, using textbooks in the ways expected by textbook writers, developing their own materials, and mediating between materials and learners in the ways advised in the professional literature? The book explores these issues from a variety of perspectives. The views of publishers/textbook writers, those contributing to the professional literature, and teacher educators are synthesised to establish a 'theory' of how teachers can best fulfil their roles vis-à-vis materials and learners. This is then compared with 'practice', as represented by published accounts of teachers' actual practices and learners' perspectives. The conclusion reached is that teacher education in materials evaluation and design is essential and suggestions are offered as to the form this might take. The book is intended particularly for MA students and teacher educators concerned with materials evaluation and design, but is of interest to all those concerned with the publication and use of English language teaching materials.