Photoisomerization in a dissipative environment is examined using optimal control within the secular Redfield approximation. With decoherence assumed rapid compared to relaxation, we find that as the environment-induced dissipation increases the optimal pulse moves towards earlier pulse times ( to take advantage of relaxation effects), shorter duration, increased power, with lower resultant target cross sections. The control mechanism is seen to change from pump-dump to pump-dump-plus-environmentally-induced-relaxation as the coupling to the environment increases. (C) 2008 Elsevier B. V. All rights reserved.