Investment in human capital is to the fore of debate and analysis in OECD countries about how to promote economic prosperity, fuller employment, and social cohesion. Individuals, organisations and nations increasingly recognise that high levels of knowledge, skills and competencies are essential to their future security and success. Investment in skills and competencies takes place in a variety of settings ranging from early childhood education to informal learning in the workplace, and involves a wide range of actors from individuals to enterprises and governments. This report aims to clarify what is now known about human capital and how it can be measured. It responds to a request by governments represented in the OECD Council "to develop an initial set of indicators of human capital investment based on existing data, analyse areas where significant gaps remain in internationally comparable data, identify the cost of development of data collection for new measures and performance indicators, and report to Ministers in 1998".