This paper develops a "capabilities approach" in asking what people are actually able to do and to be. In developing the author\u27s version of the capabilities approach as a partial account of basic social justice, she emphasizes its links with constitutional law -- saying that my account of the ten central capabilities provides a source for basic political principles that can be given more concrete form in a nation’s constitution. Her work on the approach has been illuminated by comparative study of constitutional traditions: those of India, South Africa, and the U. S. in particular. In this paper, the author shows how just one constitutional tradition – that of the U. S. – embraced, at one time, significant elements of the capabilities approach, and, more recently, has retreated from it. This case is illuminating, because it will show us how easy it is for once-admirable commitments to be interpreted, later on and in a different political climate, in such a way that they deliver merely nominal entitlements, not true human capabilities. This paper was presented at the Centre for Public Policy\u27s \u27Values & Public Policy\u27 conference in February 2009. Martha Nussbaum gained a BA from NYU and an MA and PhD from Harvard. Currently professor of law and ethics at the University of Chicago, she is considered one of the world\u27s foremost philosophers.