The definition of family farm varies across countries and contexts. We reviewed 36 definitions and uses of the term 'family farm' by academics, government and civil society organisations that describe the characteristics that make family farms unique. After reviewing these concepts we conclude that the majority of definitions recognize the role of family labour and the role of the family in managing the farm operation. However, the notion of family farming seems to go beyond farming capacity, size and orientation. The term is sometimes also used to capture ecological, social, cultural and environmental objectives and therefore has close ties to the local culture and the rural community. This paper concludes that a uniform definition of the term 'family farm' is difficult because the term is not applicable to all contexts. Instead of a definition we propose a concept of the term that highlights the most defining characteristic of family farms - the reliance on family labour - and that recognizes the linkages between its agricultural functions and its economic, environmental, reproductive, social and cultural functions. The role of family farms in food security and rural development needs to be looked at from these perspectives. This definition is the following: 'Family Farming is a means of organizing agricultural, forestry, fisheries, pastoral and aquaculture production which is managed and operated by a family and predominantly reliant on family labour, both women's and men's. The family and the farm are linked, coevolve and combine economic, environmental, reproductive, social and cultural functions.'