This IRSES project looks at why the economic and social impacts of mega events are often not realized to their full potential. The project also examines best practice in creating sustainable impacts for mega-events using a trans-continental perspective and considers cultural and other contextual differences in the perception and management of impacts. The partnership created to conduct this research includes the United Kingdom, Brazil, the United States of America, South Africa and Germany. Through examining past mega-events and attendance at current mega-events the project team will provide a comprehensive view of constraining and enabling forces affecting the management of impacts of a variety of different types (sporting and non-sporting) events. The final results of this study will provide a guide for governments and host cities to enable them to ensure the significant investment in mega-events has real and long lasting impacts for a range of stakeholders. This guide will be useful at the bidding, planning and management stages of mega-events to ensure sustainability in the legacy of those events.