This paper extends and unifies previous work on optimal contracts unde
r countervailing incentives, shedding light in particular on the relat
ion between countervailing incentives and pooling (''inflexible rules'
'). Our main result is that the nature of the optimal contract depends
crucially on whether the agent's utility is quasiconcave or quasiconv
ex in the private parameter: the optimal contract is separating in the
former case and it may entail pooling in the latter case. Journal of
Economic Literature Classification Number: D82. (C) 1995 Academic Pres
s, Inc.