This research study was designed to inform the development of a new teacher assessment model. The goal of the Teacher Success Model (TSM) initiative is to develop a systematic, evidence-informed statewide model for teacher assessment. While the initiative included all teachers, support professionals, and evaluators, this study focused on induction teachers and their mentors/administrators. Overall, our findings suggested that participants could find examples of key attributes in videos of teaching practice and that group reflection and discussion about the practices in the videos enabled everyone to develop their understanding of what constitutes evidence of effective teaching. Findings from this study will guide further development of the TSM assessment model into a multi-faceted, evidence-informed, teacher-participatory model of assessment appropriate for higher stakes decision-making. (Contains 2 tables and 2 figures.)