Educational equity is often discussed as a moral issue. Another way to think about equity is as a way to promote productivity and economic efficiency. Traditionally, equity and efficiency are viewed as competing goals. One can be fair in devising a policy, but it often happens that what is fair is not economically efficient. Conversely, what is efficient may not be fair. What is remarkable is that there are some policies that both are fair--i.e., promote equity--and promote economic efficiency. Investing in the early years of disadvantaged children's lives is one such policy. A large body of data from economics, biology, and psychology shows that educational equity is more than a social justice imperative; it is an economic imperative that has far-reaching implications for the nation. Taking a hard look at the economic value of efforts to create human capital helps people see where best to invest their resources in education to achieve its ideal--equalizing opportunity to build greater and enduring value for all. The evidence is quite clear that inequality in the development of human capabilities produces negative social and economic outcomes that can and should be prevented with investments in early childhood education, particularly targeted toward disadvantaged children and their families. (Contains 2 footnotes and 11 endnotes.)