Despite a lack of scientific evidence supporting the use of single-sex education, the number of US public schools offering single-sex education has increased. However, our understanding as to why decision-makers have implemented single-sex education is lacking. To address this gap, we surveyed US public school principals and assessed their attitudes about and experiences with single-sex schooling. Sixty-seven principals from single-sex schools and 193 principals from co-educational schools participated. The results indicated that principals who had experience with single-sex schooling tended to have more positive attitudes about single-sex schooling, viewed it as more effective, and more often evoked gender-essentialist rationales for the use of single-sex schooling than did co-educational principals. However, both single-sex and co-educational principals noted issues with single-sex schooling. It was concluded that single-sex schooling is not a silver bullet to educational reform and that when single-sex schooling is implemented, one set of issues and problems is substituted for another.