Transswitching is a variant of classical conditioning that entails the use of tonic stimuli of relatively long duration in addition to briefer, phasic stimuli which are paired or not paired with the unconditioned stimulus. The same conditioned stimulus can be conditioned to different conditioned responses in different environmental contexts. Using the transswitching procedure, the salivary response to food cues in two obese subjects was modified. The switching agent determined the relative amount of salivation. Techniques that alter alimentary responses to environmental food cues may be helpful in the treatment of obesity.