Theoretical models of mate choice and sexual selection typically make one o
f two simplifying assumptions. Either mate preferences are assumed to be un
iform (e.g. all females have the same preferences with respect to males), o
r mate choice is assumed to be a one-sided affair (e.g. females do all the
choosing). Recent empirical studies suggest that, in many cases, neither as
sumption holds. In this paper, we show how two-sided matching - a branch of
game theory developed in the economics literature - can be used to model m
utual mate choice with nonuniform mate preferences. The economics literatur
e is reviewed, and a number of biological applications are suggested. We ch
aracterize a systematic conflict of interest between males and females over
the optimal matchings in mutual mate choice systems. Moreover, we observe
that the component of choice that confers the most benefit in this conflict
is not choice in the conventional sense of accepting or rejecting courtshi
ps, but instead the power to choose the individuals to whom one displays.