This documentation presents the Climate, Land, Energy, and Water Systems (CLEWS) model developed for Lao PDR. The document presents such a model, its objective, scope and assumptions. The authors acknowledge the financial support from the United Nations Department of Economic and Social Affairs. The authors would like to acknowledge also the funding from UK Aid from the UK Government via the Climate Compatible Growth programme. However, the views expressed herein do not necessarily reflect the UK government’s official policies.