This Declaration is a statement of Heads of Government of Cambodia, Thailand, Lao PDR and Viet Nam for the 4th Summit of the Mekong River Commission (MRC) about the effective implementation of the 1995 Mekong Agreement, and in particular about sustainable basin development and management of water and related resources, including through the ambitious and forward-looking Basin Development Strategy 2021-2030, the finalisation and initial implementation of sector strategies for sustainable hydropower, environmental management and drought management, the updated guidance on design of mainstream dams, and guidelines for transboundary environmental impact assessment with voluntary application. The Declaration sets out also priority areas of action such as finding of innovative solutions, and cooperation with a focus on new joint and national investment projects of basin-wide significance, enable countries to support communities to adapt to changing river conditions, improved use of technology, implementing a Multiple Stakeholder Platform for the entire basin, strengthening the entire river basin management in accordance with the mandate of the MRC, maintaining and exploring innovative financing. The Declaration identifies the way ahead.