The articles here combine breadth of perspectives with a focus on the field's two major areas of work: learning environments and tutoring systems. The section on learning environments addresses issues of cognitive style, metatheoretic objectives, domain analysis, and a variety of implemented prototype systems: programming by example, Object-orientated Logo and the educational use of constraint based language. The domains of application range from single-word learning to algebra and architectural design. The section on intelligent tutoring systems (ITS) presents a spectrum of work grown out of the classic knowledge engineering paradigm, discussing principles and emerging methodologies for ITS construction: authoring shells, user modelling, and the role of machine learning. The applications reported range from elementary number knowledge to electronic circuits and complex industrial processes.