Small family farms account for 72 percent of the farms in the world. Most of these farms, in developing countries, face labor productivity gaps. One of the strategies to increase agricultural productivity focuses on implementing technical assistance programs. Using agriculture microdata, we estimate the marginal treatment effect of receiving technical assistance services. We find that technical assistance generates heterogeneous effects. On average, agricultural units receiving technical assistance increased their agricultural production by 50.4 percent. However, there is important heterogeneity of technical assistance’s effects across the production units’ unobserved and observed characteristics.