South Africa is a country in nutrition and economic transition. Undernutrition, particularly stunting and micronutrient deficiencies, coexist with overweight and obesity, which have been on the rise over the past few decades. The dual nature of malnutrition in South Africa comes with a complex series of epidemiological and health care challenges. Overweight and obesity are associated with chronic non-communicable diseases (NCDs) such as hypertension, diabetes, coronary heart disease, amongst others. In the context of food insecurity and the HIV pandemic which has been estimated to affect 2.4 % of children aged between 0 and 14 years, undernutrition persists, particularly among young children. Both forms of malnutrition are driven by factors which are biological, behavioural, societal and structural. This chapter addresses the following issues: (1) An overview of the historical context and the current socio-economic and political factors which shape food and nutrition security in South Africa. (2) An overview of the prevalence of over- and undernutrition in South Africa over the past few decades with special emphasis on the current situation. (3) How South Africa has constitutionally guaranteed every South African citizen “the right to have access to sufficient food, and the right to basic nutrition”, and how the State has adopted legislative measures to achieve progressive realisation of these rights.