Objective: This study sought to investigate teachers' perceptions of a physical activity-related professional development intervention. Design: Interview-based qualitative approach founded on the interpretive paradigm. Setting: Purposive selection of one high-rated independent, and one low-rated public primary school from Auckland, New Zealand. Method: A qualitative approach was used, incorporating a questionnaire used for purposive sampling and a total of eighteen semi-structured interviews with six teachers from two primary schools. Results: Participants highly valued the inclusion of all teachers in onsite professional development and felt supported by a strong, positive organizational culture. Conclusion: Participant teachers believed physical activity played an important role within the school setting, and recognized their role in the provision of opportunities for their students. However, they did not necessarily feel confident and competent to facilitate opportunities. A specific professional development intervention was introduced as one form of support to address this need. Teachers valued first-hand experience of professional development and reported particular enjoyment if they participated alongside their colleagues. (Contains 1 figure.)