Although cognitive psychology showed much initial promise, it has failed to make significant contributions to the study of human-computer interaction, which has led to a rejection of cognitivism in favour of situated action theory. The authors accept that the critique has much to offer, but reject the outright abandoning of cognitivism. Cognitive psychology needs a common language in which to describe interaction between people and artifacts: two examples of research in progress are described, one focused on events, the other on representations and the relationship between the information display and the conceptual model. Cognitive psychology also needs a better delivery method than the traditional research paper, and the idea is proposed of a vocabulary of ‘cognitive dimensions’, terms which can be meaningfully used by non-specialists (who will recognise familiar but uncrystallised concepts) and which can be used as indexes to the professional literature. These two components form a proposal for improving the effectiveness of cognitive psychology. The paper ends with the hope that mainstream cognitive psychology will broaden its area of enquiry.

Software engineers have developed sophisticated “object‐oriented” programming environments that are intended to make the reuse of program code easy. Experience has shown that these environments can be improved: Even very experienced programmers have problems in locating and comprehending code for reuse. Programs cannot be modified as readily as had been anticipated. We describe the problems in terms of “cognitive dimensions” of notational systems and show how improved support for opportunistic design may be achieved. A central tenet is that programmers are not at present able to externalize enough of their knowledge about a program. We propose a scheme for attaching a “description level” in which arbitrary attributes and relationships can be recorded in a “browsable” form. Our conclusions stress improving the means for programmers to represent facts rather than the provision of predefined knowledge bases.