Ranjay Gulati is the Paul R. Lawrence MBA Class of 1942 Professor and the former Unit Head of the Organisational Behaviour Unit at Harvard Business School. In his new book, Deep Purpose: The Heart and Soul of High-Performance Companies, he argues that companies must embed purpose more deeply than they currently do, treating it as a radically new operating system for enterprise. At a time when many have become cynical about purpose, Gulati documents the vast performance gains that purpose-driven companies achieve as well as the social benefits they deliver. In this interview, I speak to Professor Ranjay Gulati about deep purpose, leadership, and his field research in organisations including Etsy, Lego, Warby Parker, Mahindra, Microsoft and the Seattle Seahawks. Gulati discusses how long-term value and short-term performance need not conflict but rather, when leaders go deep on purpose, high-performance and durable profits typically follow, delighting all stakeholders. Deeper engagement with purpose holds the key, not merely to the well-being of individual companies, but to humanity’s future.