These hypotheses are then tested with data from approximately 60 countries. The results suggest that a relative undersupply of women (i.e., a high sex ratio) decreases significantly women's criminal offending rate (as indicated by the ratio of female-to-male arrest rates for theft). The hypothesis that the sex ratio increases the protection from crime afforded women (as indicated by the percent of rape cases solved by police) receives guarded support. These findings accord with the sex-ratio thesis, which suggests that in high sex-ratio societies women will be highly valued and their roles limited to the family, where opportunities to commit crime are minimal. Contrary to our hypothesis, however, the sex ratio does not significantly influence the female homicide victimization rate. Finally, the level of socioeconomic development, as measured by a multi-item index, is shown to have a substantial influence on sex differences in homicide victimization and theft offending. (Author abstract)