Economic development is aimed at improving the well-being of the people of the earth. But how do we understand the notion of human wellbeing? What is involved in improving a person's welfare? What is a human life, lived well? Such questions are foundational. Without compelling answers to this set of questions, we will have no convincing basis for advocating one form of economic development or another or assessing the obligations and rights that the various agents within the global economy have. Answers to these questions should serve to define the most fundamental priorities that ought to lead our thinking about economic development.