Rats ran from an alley where they received a continuous shock of 250 v. to a goal-box where they received a continuous shock of either 50, 150, or 200 v. for 20 sec. Escape performance was an increasing function of amount of shock reduction. The results are analogous to those obtained by Crespi (see 17: 1494) and Zeaman (see 24: 1733) with appetitive rewards and suggest that similar behavioral laws underlie both instrumental appetitive and escape conditioning. (PsycINFO Database Record (c) 2006 APA, all rights reserved)