Today, attention is focused on the critical role principals play in creating contexts for learning that result in measurable student growth. This study was designed to explore and describe current principal evaluation practices in Wisconsin and determine, in what ways and to what extent, these systems advance the practice of principals towards mastery of accepted leadership standards in the field. The intent of this mixed methods study was to use results to inform the design and implementation of principal evaluation practices that can serve as a mechanism for advancing the principal's practice towards higher levels of proficiency and thus, positively impact teacher and subsequently student performance. Findings from the survey suggest that principal evaluation practices in Wisconsin only support principals' ongoing development to mastery of practice to a limited extent. Analysis of case sites reflected promising principal evaluation practices for advancing the principal's practice towards mastery which include, formative feedback processes and professional development mechanisms that support growth towards mastery of identified leadership standards for principals.