This paper examines the history, activities and future interests of the UNITWIN/UNESCO Chair on Reorienting Teacher Education to Address Sustainability and the associated International Network (IN) of Teacher Education Institutions. In 1998, the United Nations Commission on Sustainable Development work programme on education for sustainable development (ESD) requested UNESCO to develop guidelines for reorienting teacher training to address sustainability. This responsibility was passed to the UNITWIN/NESCO Chair who established the IN. Participants recorded their efforts in journals, chronicling successes and failures. In 2004, IN members were sent a survey requesting information about what worked, what did not work and insights and recommendations for other institutions of teacher education. The responses were synthesized in "Guidelines and recommendations for reorienting teacher education to address sustainability". Several UN agencies and regional offices have incorporated these "Guidelines" into their efforts. Members of the IN are now engaging other institutions of teacher education through workshops and mentoring to reorient teacher education.