What do we mean by rights, and can our use of the concept be justified? This book offers a partial vindication of the concept of a right, defending its use in relation to human rights while questioning it in relation to property. It starts with a new ‘Addressive’ account of the nature of rights as bringing together duty-bearer and right-holder first-personally—a theory which moves beyond and complements traditional Interest and Will Theories. This Addressive account implies that a right exists pre-institutionally (as a ‘natural’ or ‘moral’ right) only when a duty owes its existence predominantly to the right-holder’s good. On this basis, the book defends human rights law and practice as justifiably institutionalizing certain pre-legal moral rights held against other individuals and the state, including socio-economic rights. This defence proceeds independently of whichever conception of ‘the important human features’ (e.g. agency, capabilities, freedoms, interests, needs) one takes to underpin human rights—though it does depend on a distinction between individual and other goods. The book ends by arguing that for much property, conceiving the relevant duties in rights terms can mislead us into overlooking their foundation in the collective good. An alternative non-rights property system—broadly resembling modern markets but not conceived in terms of rights—is outlined. The result is a defence of the rights concept that is more supportive of human rights than many of their critics (from left or right) might expect, while pressing new doubts about much property as an individual right.