Despite increasing research efforts, there is still much confusion regarding the nature and contribution of the most intangible forms of capital. This book develops a comprehensive and unifying conception of intangible capital in order to understand its role with respect to economic growth, well-being, and rationality. As the book illustrates, utilizing the intangible capital concept enables many new and important economic insights. Intangible capital is defined to include standard human capital, noncognitive human capital (including personal capital), social capital, and other intangible manifestations of human capacity. Understanding intangible capital is a key to realizing the full human potential of our economic systems.