This chapter starts with a definition of anti-discrimination policies and introduces a number of dimensions along which they differ before zooming in on a particular form of anti-discrimination policy: affirmative action. This is motivated by how many other forms of anti-discrimination policies are comparatively uncontroversial and raise less interesting moral questions, whereas affirmative action seems vulnerable to the apparently decisive reverse discrimination objection. Hence, I consider and rebut this objection before proceeding to review some other objections to and some of the most important justifications for affirmative action. While generally favourable towards affirmative action, this review is somewhat open-ended, since the question ‘Is affirmative action justified?’ is posed at a level of generality which is too high for it to have any plausible ‘Yes’ or ‘No’ answer. The chapter ends by suggesting that anti-discrimination policies extend beyond the labour market and higher education.