Social security is a system which stabilises the living standards of the nation as a whole through social means. Social insurance is a system that collects contributions as reserved money from a large number of people by various methods, applying probability calculations and redistributes the funds in the form of various kinds of benefits; in other words, cash benefits or benefits in kind, which relate to the livelihood and economy of the nation. But in reality, "Who should be assured or cared for?" and "How should we organise our lives?" are still the most important socio-economic problems to be solved in Japan. One of the features of the social security system in Japan is the comprehensiveness of its benefits. On the other hand, as there is inadequate unification and co-ordination among various social insurance schemes, there is great disparity, inequity and inequality among them. It is imperative to reform the social security system, including health insurance, because most of the nation can hardly make a greater personal provision for life, particularly life after retirement, in this era of uncertainty. The philosophy of reform should be that the basic needs of life that are common to all, which are based not on absolute but on relative criteria, must be met.