This report explores the concept of sustainable and responsible tourism, focusing on the role of leading global organizations like the World Tourism Organization. It discusses the definition of sustainable tourism, the evolution of sustainable and responsible tourism, and the role, function, and mission of the World Tourism Organization. It also analyzes the concepts and meaning of sustainable and responsible tourism, as well as the significance and application of these concepts. The report further evaluates the purpose and principles of tourism development and the challenges associated with it, using specific examples from Vietnam. Finally, it critically evaluates different approaches to tourism development and the rationale for measuring and monitoring sustainable performance.