The paper uses a stochastic frontier analysis of production functions to estimate the level of technical efficiency in agriculture for a panel of 29 developing countries in Africa and Asia between 1994 and 2000. In addition, the paper examines how different components of an agricultural innovation system interact to determine the estimated technical inefficiencies. Results show that the mean level of technical efficiency among the sampled countries was about 86 percent, with some modest increases during the period in question. These results suggest that there is room for significant increases of production through reallocations of existing resources. Despite significant variation among countries, these results also indicate quite a number of least developed countries have high mean efficiency scores, implying a need to focus on investment that pushes the production frontier outward in these countries. Several measures of agricultural R&D achievement and intensity, along with educational enrollment, are found to enhance agricultural efficiency. On the other hand, countries with higher levels of official development assistance, foreign direct investment, and a greater share of land under irrigation are found to be performing poorly in their agricultural efficiency score.