ABSTRACT Human capital theory is the dominant theory of education in economics. Earlier writers such as Adam Smith, John Stuart Mill and Alfred Marshall highlighted a variety of roles for education, but human capital theory, which was formalised in the 1960s only examined labour-productivity improving skills. Other dimensions of education, which add complexity to the economic analysis of education, have been overshadowed by the focus on quantifying education’s economic value. These other dimensions include education’s role as a driver for individuals to improve their personal lives and avoid poverty. John Kenneth Galbraith and Amartya Sen supported this broader notion of education. Sen combined a multidimensional approach to education with the human capability approach, which centred around the person rather than the worker. This review highlights that crucial aspects of education have been disregarded during the formalisation of a unitary theory, and therefore are missing in empirical research.