This study analyses the importance of sustainability in tourism and how it can be implemented in the management of tourism projects and destinations through a clear and structured methodology utilising the PM4SD (Project Management for Sustainable Development) approach to project implementation. The methods applied to this paper focus on a review and evaluation of the CoLead project and its effectiveness in transferring sustainable tourism projects from theory into practice. This study is based upon two case studies, in Bulgaria and Wales and have adopted a broad qualitative approach based upon in depth interviews with key protagonists and participants associated with the project. The paper's findings raise questions regarding broader applicability, sustained support, stakeholder participation and long term management and funding for the continuation for such projects. In this respect the paper concludes with broader lessons that can perhaps be learnt from projects such as CoLead