Education is expected to support the development of a more sustainable way of thinking, working, and living. Although there is a broad range of literature on Education for Sustainable development (ESD), the role of principals in the implementation of sustainability and ESD in schools has rarely been taken into consideration. However, based on the results of school effectiveness research, one can assume that school principals exert a significant influence on ESD. Sustainability is a leadership issue. When a school aims at integrating sustainability and ESD, the principal plays a pivotal role. She or he has to support the endeavor wholeheartedly and credibly, organize a participative process of school development, push ahead sustainability and ESD in the daily life of the school, support teaching staff in the application of ESD, involve students and offer them opportunities to launch their own initiatives. This article seeks to support principals in leading their schools towards sustainability. Four stages of the integration of Sustainability and ESD in a school are defined. For each of these stages, a number of actions and management strategies are suggested and explained in detail.