The concept of need is commonly overlooked by philosophers and social scientists. Often considered exclusively instrumental and/or demarcating minimal attainments, needs are commonly allowed only a minor role in accounts of well-being and related moral and political theories. While this may be true of some conceptions of needs, this thesis defends the critical importance of a different kind of need. These ‘personal needs’ fulfil all necessary conditions for genuine needs, but instead mark out ultimate ends that are far from basic. Moreover, rather than representing preconditions for the lives of human beings in general, personal needs are specific to individuals. Yet also unlike subjective preferences and aims, personal needs are the requirements of things a person is objectively committed to and cannot give up. // Personal needs directly relate to a person’s private evaluation of their own life. Yet they also have wide relevance to other contexts of evaluation within and without philosophy. They play a structural role in a new framework for conceptualising well-being and its role in ethics and policy. In particular, personal needs introduce incommensurability into the fundamental structure of persons’ interests. Located in the same context of individual choice as utility theory, they represent a direct, fundamental challenge to formally monistic teleological conceptions of well-being prevailing in much of social science, policy, and philosophy. Among various potential connections, this framework promises to (a) make sense of some people’s claims that they cannot be compensated for certain losses, (b) help motivate the incommensurability claimed to exist between dimensions in multidimensional well-being measurement (including those drawing on the capabilities approach), and (c) inform approaches to interpersonal distribution that oppose aggregation. This thesis also touches on issues concerning the concept of well-being, the objectivity or subjectivity of well-being, axiology, and coherentist practical reason
