On average, men tend to start earlier, perform better, and persist longer than women in the chess domain. Similarly to several other domains, such as those related with STEM fields (science, technology, engineering, and mathematics), women are highly underrepresented in the chess domain. The marked difference in the amount of men and women participating in chess, has led to the assumption that the differences in chess performance between men and women is due to a statistical effect derived from the differences in participation rates. In contrast, other findings suggest that men might have an innate advantage or better predisposition for chess playing, enhanced by certain cultural factors. Some differences in the chess playing of men and women that have been reported in relatively recent studies are also highlighted. The chapter closes by presenting a statistical analysis that compares sex differences in chess performance at different levels of practice, which suggests factors other than practice as the underlying causes of these sex differences.