First, this was essentially the structure of the Japanese health insurance system. Second, the Park government considered the decentralized health insurance system as an intermediate step between a completely private voluntary health insurance system (e.g., health maintenance organizations) that would emphasize cost containment and a state-administered health insurance system (e.g., single-payer NHI) that might place substantial financial burdens on the state. Third, the bureaucratic machinery to administer an NHI system just did not exist within the Korean government in 1977, when President Park decided to mandate healthinsurance for large employers. Therefore, medical insurance societies appeared to be the best vehicle for gradually extending health insurance to the whole nation.