Active and retired federal employees, together with their dependents, represent the single largest group of persons enrolled in any voluntary health insurance program in the United States. The extent of their coverage and enrollment is of particular interest to physicians in California since this state has the largest proportion of all federal employees enrolled among all states. Of the almost 5(3/4) million federal employees and their dependents, enrollment in California was almost 609,000 or slightly over 10 per cent of all those covered. Better than 3 out of 5 individuals covered were enrolled in service type plans both in the U.S. and in California. Of all persons enrolled in comprehensive group practice and individual practice plans in the U.S., almost one-half were in California alone. Almost 4 out of 5 individuals enrolled were in high option plans. "... an indication that most employees were satisfied with their initial choice of plans."