This paper examines changes in agricultural productivity in 18 developing countries over the period 1961-1985. We use a nonparametric, output-based Malmquist index and a parametric variable coefficients Cobb-Douglas production function to examine, whether our estimates confirm results from other studies that have indicated declining agricultural productivity in LDCs. The results confirm previous findings, indicating that at least half of these countries have experienced productivity declines in agriculture. © 1998 Elsevier Science B.V. All rights reserved.