Equity is the absence of avoidable or remediable differences among groups of people, whether those groups are defined socially, economically, demographically or geographically. Health inequities involve more than inequality with respect to health determinants, access to the resources needed to be healthy or health outcomes. They also entail a failure to avoid or overcome inequalities that infringe on fairness. Reducing health inequities is important because health is a fundamental human right. However, evidence suggests that the impressive health gains achieved over recent decades are unequally distributed and have largely failed to reach the poor and other marginalized or socially excluded groups. Persistent and growing inequalities in health are increasingly evident, both between and within countries.