The Collaborative Action Coaching for Leaders model (Cook, 2011) is designed for the transfer and sustainability of learning from the coaching session to outside that experience: it is a return on investment. The model emanated from a doctoral level research study conducted with leaders from UK voluntary sector organisations: namely Advance, Mencap and Rethink. The study found that both the coach and the leader have individual and shared responsibilities in the transfer and sustainability of learning, and this paper describes the research study as well as the model emerging from the author researching her own external coaching practice.