The ongoing exodus of rural people to urban areas in developing countries has led to rapid and massive increases in the urban population. Often rural emigration results in the transfer of poverty, hunger and malnutrition from the countryside to towns and cities, a process known as the “urbanization of poverty”. To meet their food needs and to supplement their incomes, many urban inhabitants—especially those newly arrived from the countryside— practise urban and peri-urban horticulture (UPH) on vacant lots, in backyards, along rivers, roads and railways, and under power lines. Governments and city administrations need to recognize the opportunities offered by UPH to improve urban food security and livelihoods.