This Paper analyses how agrarian structure influences food and nutrition security in rural versus urban areas of Low and Lower-Middle Income Countries. It is highly relevant to the discourse in development studies about urban-bias, smallholder focused rural development, and rapid rural-urban migration. I use the Comparative Configurative Method in a fuzzy-set analysis of how the prevalence of smallholder farming influences food security in different socio-economic contexts such as land concentration, type of food system, the relative size of the agricultural population, GDP per capita, and agricultural productivity. The study comprises a sample of twenty-eight countries across Sub-Saharan Africa, South and South East Asia, as well as Latin America.