Traditional approaches to computer-aided learning have tended to minimize the role of the local teacher, despite their experience and close knowledge of their students' learning needs. A new approach to producing educational materials focuses on the construction of "learning objects", storing these in "digital repositories" and allowing for reuse in a variety of contexts. This paper reviews these basic concepts and provides information on their current state of development. It is also argued that whilst these new technologies offer tremendous potential benefits, more regard must now be paid to underlying pedagogical structures. This requires more explicit consideration of the types of learner activity and the social context within which the learning is situated. (Contains 1 figure.)