Last year, more than 1.2 billion people travelled across international borders, a trend that is only set to continue. As the number of people travelling for tourism continues to grow, UNESCO World Heritage sites are seeing their visitor numbers increase dramatically, creating enormous opportunities but also challenges for these sites and local communities. Balancing the ideals of conservation, economic development and local participation at world heritage sites is the goal of UNESCO's World Heritage and Sustainable Tourism Programme, which is led by Peter Debrine. In this episode, we sat down with Peter to talk about UNESCO's efforts to make sustainable tourism a reality, and also to hear his tips for travellers who wish to visit World Heritage sites sustainable.