Bilateral lesions of the septal forebrain interfered with (a) the postoperative establishment of discriminated shock-produced suppression of lever pressing for water reward, and (b) postoperative retention of a preoperatively established suppression. The magnitude of the interference with acquistion depended upon the intensity of the shocks employed to suppress the lever response, but differences in suppression between septal and sham-operated control rats could be offset by increasing water deprivation of controls. Septal lesions consistently increased postoperative water intake following deprivation. The major effects of the lesion on suppression of lever pressing by shock, were considered secondary to the effect on water intake.