General practice consultations were video-recorded before and after the introduction of a desk-top computer system into the practice. The recordings were analysed by detailed qualitative scrutiny of tape and transcripts (conversation analysis) to discover regular patterns of interaction. This analysis confirmed that the introduction of computers into the consultation had a significant impact on the communication between patient and doctor. In particular, we found that computer technology has had an impact on the practitioners' conduct and on the disclosure of information by the patient. The analysis also points to some recommendations both for training general practitioners in the use of computerized systems in the consultation, and for the (re)design of the technologies themselves.