In this article, we focus on a specific type of two-generation program: those that intentionally link education, job training, and career-building services for low-income parents simultaneously with early childhood education for their young children. These programs emphasize an investment strategy to build human capital for both children and parents, implying an intensive, extended approach. In the past five years, the appeal of a human capital two-generation perspective has led to a number of initiatives. Evaluation evidence for these recent innovations lags behind policy and practice, but theoretical support for two-generation programs is compelling. This article integrates theories from developmental science, economics, and education to evaluate the assumptions that underlie two-generation programs, to outline possible mechanisms through which these programs affect children, to synthesize and critique what has been tried to date, and to describe emerging programs across the nation. (author abstract)