The Working Group 5 of the International Medical Informatics Associa­ tion (IMIA) is dedicated to information systems in primary care with special emphasis on computer systems in the doctor's office. Accord­ ingly, a conference was held in Hannover in 1980 where the first ap­ proaches were described and experiences in system analysis, system construction and evaluation were discussed (Rienhoff, O. and Abrams, M.E. (eds.): The Computer in the Doctor's Office, North-Holland, Amsterdam: 1980). Computer hardware and software development has been rapid over the last years. Thus the prerequisites for a successful support of the work of the physician in his office have improved. But system con­ struction still lags behind and the actual penetration of systems is lower than 2 % of the doctors' offices in most countries. This applies to industrialized countries. However, attempts are made everywhere to improve primary care by means of modern information technology. Information systems depend upon the real environment into which they are placed: administrative procedures govern priorities and procedures in doctor's office computers, possibilities to defray cost upon the various carriers or the patients have a great influence on the propagation of systems. Furthermore, various procedures of accounting or re-imbursement may lead to a facilitation or to a delay of the in­ troduction of systems. The 'art of medical practice' has reached a comparable standard within at least the industrialized countries.