The article analyzes the relationship between the concepts of the common good, public interest, individual (private) interest, and the problem of reconciling individual interest and the common good in the theory of state solidarism. The authors reveal the concepts of solidarism and solidarity at different stages of the development of social thought. The importance of updating the solidarity strategy for modern society is argued. The ideology of solidarism did not have full development in the 19th century – in contrast to the complete ideologies of liberalism, social democracy, and conservatism. However, in a postmodern society, solidarism can increase its attractiveness. The ideas developed in the philosophy and ideology of solidarism (solidarity, trust, cooperation, subsidiarity, self-organization, non-hierarchical interaction) can provide an answer to many actual challenges of our time.