Are the sexual desires of males and females similar or different? This is a question of both practical and intellectual significance. The various sciences of sexual desire—anthropology, sociology, physiology, evolutionary psychology, zoology, and contemporary psychiatry—make pronouncements about differences and similarities between the sexual desires of males and females. In some domains, such as that of evolutionary psychology, the claim that males and females differ in sexual desire is a core theoretical commitment, and proponents have appealed to a massive volume of empirical evidence for this claim—I call this the ‘standard view’ about sex differences in sexual desire. However, there are two fundamental challenges to theorising about the standard view: one ontological, the other epistemological. The ontological challenge holds that our sexual desires are the product of social forces and norms, and thus the standard view can at best reflect social rather than natural causes. The epistemological challenge holds that the relevant evidence underdetermines conclusions about sex differences in sexual desire, and our theorising about the standard view is permeated by social values and cultural norms. There has been, though, a second wave of empirical work which deploys methods designed to mitigate the threat of bias and underdetermination present in the first wave. Some of this more recent evidence contradicts the standard view, suggesting that natural sex differences in desire are minimal. In this paper I articulate competing positions on the standard view, describe some of the relevant empirical work, and formulate and assess the key arguments of both proponents and critics of the standard view, ultimately concluding that sex differences in desire exist, but are not nearly as pronounced as the standard view holds.