The Integrated Green Economy Modelling (IGEM) framework is designed to serve three purposes: (1) it builds on UN Environment’s past country experience with modelling green economy policies, including the application of the T21 model, to answer increasingly complex requests from governments; (2) it supports the endowment of countries with solid quantitative tools to inform the design and implementation of green economy policies; and (3) it advances the process of implementing and monitoring some of the Sustainable Development Goals (SDGs). The IGEM framework presents a methodology on how to integrate three of the main modelling techniques used for green economy policy assessment to refine impact analysis of green policies and investments in the economy. It presents the linkages between a system dynamics (SD) model and a computable general equilibrium (CGE) model, building on input-output and social accounting matrix (IO-SAM) models.