Although land plays a crucially important role in economic development and structural transformation, the causes and consequences of the evolution of farming land have only been paid scant attention in recent decades. In this paper I document changes in the extent of global farming land and in average farm sizes. I show that the spatial distribution of global farming land has changed dramatically, with developed countries substantially reducing their share and landabundant developing countries substantially increasing their share. In per capita terms we see a rather different pattern, with average farm sizes increasing rich and more commercialized agricultural systems, and generally declining or staying constant in poorer and less commercialized systems. These outcomes are the result of complex processes that are not always well understood. I conclude the paper by suggesting new, or neglected, areas of research that would help us better understand these critically important developments.