The crystal structure of the ternary complex of horse liver alcohol dehydrogenase (LADH) with the coenzyme NADH and inhibitor dimethyl sulfoxide (DMSO) has been refined by simulated annealing with molecular dynamics and restrained positional refinement using the program X-PLOR. The two subunits of the enzyme were refined independently. The space group was P1 with cell dimensions a = 51.8, b = 44.5, c = 94.6 A, alpha = 104.8, beta = 102.3 and gamma = 70.6 degrees. The resulting crystallographic R factor is 17.3% for 62 440 unique reflections in the resolution range 10.0-1.8 A. A total of 472 ordered solvent molecules were localized in the structure. An analysis of secondary-structure elements, solvent content and NADH binding is presented.