Few studies have involved an examination of behavioural gender differences among callitrichid primates. The present paper presents consistent evidence from experimental projects, together with less formal observations, that adult females of both breeding and non-breeding status in species of marmosets (Callithrix) and tamarins (Saguinus) demonstrate priority of access to preferred and/or restricted sources of food. Differences in behavioural strategies between males and females in this regard are not only functionally plausible, but are consistent with differences in natural behaviour both in feeding ecology and social organization in species of the different genera. Behavioural propensities that relate to the behavioural strategies of males and females are also considered, together with a number of suggestions for future research that arise directly from the observations reported.