This paper examines the management of private insurance economy and the ambivalence between ‘social’ and ‘commercial’ dimensions of insurance. The paper analyzes the issue by exploring five different techno-institutional practices of insurance. These are, first, pricing of the coverage (equal distribution of risks vs. risk classification), secondly, investment practices (social investment policy vs. market-based investment policy), thirdly, the form of the product (risk insurance vs. savings insurance), fourthly, the purpose of the organization (insurance company vs. bank), and finally the company form (mutual company vs. stock corporation). The main question of the paper is: in what ways is insurance solidarity enacted and economized within insurance industry? The paper studies the question by exploring the changing insurantial imaginaries and practices in Finland from 1940s until 2000s. The study is based on the analysis of published talks, interviews and writings of the ‘insiders’ in the field, i.e. executives and officials of private insurance companies, their interest groups and supervisory authorities. The paper aims to provide an in-depth analysis of the entanglement of economic, political and scientific rationalities in the management of insurance economy.