Poverty has long been a concern in public health with people living in poor circumstances generally suffering higher burdens of disease. Understanding the persistence of poverty, and of its impacts on health, unavoidably intersects with analyses of how inequalities arise in the distribution of income and wealth, and of the material and psychosocial resources these socioeconomic privileges accord. This chapter reviews different definitions of poverty, trends in the distribution of absolute and relative poverty, and strengths and weaknesses of the different concepts. It touches briefly on how poverty (by whatever definition) influences health, citing natural/social selection, cultural/behavioural, and materialist/structural explanations; and discusses how, in some instances, there is reverse causality with poor health worsening individual or household poverty, particularly in low-income countries suffering high disease burdens and weak health systems. The chapter then turns to a review of major theories of justice and how these argue for interventions, and the role that international human rights might play in furthering actions to reduce poverty-related health inequalities. It concludes with a short discussion of different sociopolitical approaches to poverty reduction, providing three examples of intervention policies.