This paper takes the position that language learning materials should ideally be driven
by learning and teaching principles rather than developed ad hoc or in imitation of
best selling coursebooks. It briefly reviews the literature which contributes positively
towards the principled development of ELT materials and comments on its
implications for materials writing. It then presents six principles of language
acquisition which the author thinks should be given a lot more attention in materials
development. It outlines and justifies each principle and then derives from it materials
development principles and procedures which teachers and materials writers could
apply to the actual development of materials.