In 1992, most members of a Swiss indemnity health insurance plan were automatically transferred into a newly created managed care organization. This study examined whether this semivoluntary change affected enrollees' health status and satisfaction with care. Three groups of enrollees were compared: 332 plan members who accepted the switch (managed care joiners); 186 plan members who opted to maintain indemnity coverage (non-joiners); and 296 persons continuosly enrolled in another indemnity plan (indemnity plan members). Health status, health related behaviors, and satisfaction with care received in the previous year were surveyed at baseline and 1 year later. Health status remained unchanged in all three groups. Smoking prevalence decreased among managed care joiners but remained constant in the other groups. Satisfaction with insurance coverage increased between baseline and follow-up in managed care joiners, but decreased in nonjoiners and indemnity plan members. The latter groups had higher satisfaction with health care, particularly with continuity of care. A semivoluntary switch from indemnity health insurance to managed care reduced satisfaction with health care but increased satisfaction with insurance coverage. There were no changes in self-perceived health status.