This work deals with the optimal control of a rougher flotation circuit. The optimization of this process plays an important role in the improvement of a concentrator plant efficiency, since even small increases in the valuable recovery mean an important economic impact. In order to exploit the serial structure of this process, the dynamic programming technique is used. The optimization problem is solved considering phenomenological models for each flotation bank of the circuit, validated using process data obtained from several sampling surveys carried out in a rougher flotation circuit of a Chilean mineral processing plant. The control objective is the minimization of the Cu tailing grade in each bank given a final Cu concentrate grade. Simulation results show a good correspondence between the proposed optimization strategy and the actual operating practices at the rougher flotation plant under study, considering different operational scenarios. (C) 2006 Published by Elsevier Ltd.