With the objective to help “demystify” the importance of environmental and social (E&S) considerations, and their integration into the project development process and financing timeline of infrastructure projects in the Mekong subregion, this Tutorial is a simple and accessible guide that aims to familiarize stakeholders of varying backgrounds with supporting sustainable infrastructure development. This is especially relevant for the Mekong subregion with infrastructure playing a central role in economic, social and environmental development.