The studies available on the subject of choice of health insurance plans deal with the dual choice situations in which members of an employment group are offered a choice of two different plans, one of which usually provides comprehensive care by a group practice closed panel, the other freedom of choice of physician, with more limited benefits. The study reported here examines the situation when an employment group is offered a choice between a variety of plans with different organizational characteristics and extent of coverage. Demographic characteristics of the enrollees, characteristics of the plans, and knowledge about the extent of coverage are examined in relation to the decision to choose or change plans.