Abstract: Using detailed household-farm level data from Malawi, we measure real farm total factor productivity (TFP) controlling for a wide array of factor inputs, land quality, and transitory shocks. The distribution of farm TFP has substantial dispersion but factor inputs are roughly evenly spread among farmers. The striking fact is that operated land size and capital are essentially unrelated to farm TFP implying a strong negative effect on agricultural productivity. A reallocation of factors to their efficient use among existing farmers would increase agricultural productivity by a factor of 3.6-fold. We relate factor misallocation to severely restricted land markets as the vast majority of land is without a title and a very small portion of operated land is rented in. The gains from reallocation are 2.6 times larger for farms with no marketed land than for farms that operate marketed land.