The notion of learner‐centred instruction in foreign and second languages grew out of the recognition that language learners are diverse, in their reasons for learning another language, their approach to learning, and their abilities. This article is about learner development, a learner‐centred innovation in FL/SL instruction that responds to learner diversity by aiming to improve the language learner's ability to learn a language. First, an overview are provided. Then, the foundational ideas that shaped early practice in learner development and the changes in the field that resulted as these ideas were implemented in language programmes in various world regions are described. An evaluation of the theory and practice in learner development from the perspective of selected theories in SLA follows. The conclusion provides suggestions for future development.