This paper describes the action research process aimed at identifying the information systems requirements of a New Zealand health supplier. In part, this is in response to the recent changes in the New Zealand National Health System and the lack of success of previous implementations of commercial solutions. The study is the product of the urgent necessity of offering better services with more competitive costs, based on the specific requirements of stakeholders (medical, administrative staff). The focus of the requirements is found in the concept of the patient as the generator of the whole system and the centre of information. The creation of a 'Patient Management Information System' (PMIS), and its interaction with different stakeholders, is the recommended outcome of the action research process. The process by which a phased introduction of the PMIS can be implemented, in order to reduce its impact on work practices, is then outlined.