The aim of the study was to obtain more insight into the organizational and environmental determinants of the implementation of quality management in health care organizations. Primary survey data were collected in 1995 in a large nationwide study within 15 fields of health care and health care-related social services in The Netherlands. In general, there are more differences between health care organizations than between fields of health care. Environmental influence was found to be less important than was expected. Care-oriented organizations have a greater opportunity to involve their patients. It seems that apart from patients, the perceived pressure from other third parties has little influence on the implementation of quality management in health care organizations.