This paper uses a quantitative approach to examine the effects of age and gender on liquid assimilation, a regional feature of Cuban Spanish. The first research question addresses the diffusion of liquid assimilation and compares two generational groups to establish that there has been a change in progress, and to gauge its advancement in the speech of younger individuals. The second research question examines gender patterns for (r) and (l) and compares these to determine whether assimilation is the same for both liquids. Although most linguistic variables show gender differences, a significant effect of gender was found for (r), but not for (l). It is argued that (r) is more salient than (l), and that this contributes to the gender patterning found here. These results suggest that assimilation is a change from below that has been led by men. The factors that contributed to the spread of assimilation and to its development in the speech of men are discussed.