Although principal professional development (PPD) has been proven to improve school performance at various levels, professional development (PD) for teachers receives more time, resources, and attention at both district and state level. When PPD is provided it often does not meet research-based recommendations. The literature was reviewed and five criteria areas with multiple indicators for effective PPD outlined; these were subsequently revised and validated by experts in the field. The PPD certification policies of each U.S. state that made this information publicly accessible was examined through Department of Education websites, with clarification by phone when necessary. This study revealed that only one state met all indicators, and that most states did not have comprehensive, research-based PPD policies. Given the significant effect school leadership has on student achievement and school improvement, further research on PPD implementation should be prioritized.