This paper estimates required investment and its allocation among different regions to maximize agricultural output gains and poverty reduction. The analysis uses a social welfare function to simulate the optimal allocation of research and development (R&D) investment across developing regions (1) to maximize agricultural growth or (2) to maximize poverty reduction at the global level. Due to uncertainties of the parameters used, sensitivity analyses was conducted to evaluate the effect of different values of R&D and poverty elasticities on the optimal allocation of R&D investment across regions. Our simulation results are robust for a wide range of parameters and show that to maximize agricultural output growth in developing countries, R&D investment should be allocated mainly to Southeast Asia and South Asia, whereas to maximize poverty reduction, priority should be given to Sub-Saharan Africa and South Asia.