The Population Research Institute carries out research in  population studies, family sociology, and sexology. We study family formation, childbearing and childlessness, the integration of immigrants, and couple relations, sexuality and sexual well-being. The annual Family Barometer Survey covers key issues in family life and policies. The PRI also publishes the Finnish Yearbook of Population Research.

The library and information service of Väestöliitto serves both customers outside the organization as well as Väestöliitto's staff.