This paper proposes an analytical framework to list and study the role of key long term drivers of food and nutrition security (FNS). We start by identifying what are the key variables affecting food and nutrition security at the household and the country level, and then define what are the main exogenous or endogenous drivers impacting these variables. We discuss the key drivers of both aggregated food supply and demand, and therefore the consequences on prices. Specifically for aggregated food demand we discuss demographic increase, income growth, changes in preferences, aggregated domestic distortions and overall quality of the food system. With respect to the drivers of aggregated food supply we discuss the land available for food products and drivers behind land availability, the share of waste/losses generated by the food system, and the normalized average yield. We define yield as the amount of nutrients produced by unit of land. It depends both on the physical yield of the crop or the livestock, and also on the quality of the food and it can be affected by the changes in production patterns linked to the different dietary patterns of the consumers and by climate change. We emphasize the fact that in many cases, key drivers may have ambiguous effects on the food and nutrition security situation of different agents. For instance, more liberal trade policies will affect real income, terms of trade, demand and supply, returns of factors, foreign direct investments and food prices, thus may lead to the improvement of global level FNS, i.e. the FNS of a majority of people on Earth. However, at the same time, more liberal trade policies may bring food insecurity to some households. Therefore, careful quantitative assessment is needed for each policy option. Finally, we also propose a typology of variables that will help modelers adapt their models to study the different drivers, through both direct and indirect effects.