This formative research study was designed to inform the development of the Teacher Success Model (TSM), an initiative to develop a systematic, evidence-informed model for teacher assessment. While the overall initiative includes all teachers, support professionals, and evaluators, this study focused on induction teachers and their mentors/administrators. Participants were shown sample digital videos corresponding to seven pre-selected TSM attributes, and were asked to identify, annotate, and rate instances where specific attributes were evident. Overall, our findings indicated that participants could identify examples of key teaching attributes in the videos and that group reflection and discussion enabled many to refine their understanding of evidence in assessing teaching. These findings will guide further development of the TSM assessment model as a multi-faceted, evidence-informed teaching assessment model.