Book excerpt: In the fast-changing policy arena of a country as diverse as India, gauging regional implications of policy shifts is critical but challenging. E3-India is a policy evaluation tool based on the internationally recognized E3ME global model, that allows for iterative quantification of multiple policy options within an integrated economy-energy-environment framework to support wellinformed progressive policy choices at the regional level. This book provides comprehensive coverage of creating and using E3 modeling framework for regional policy analysis, which is available in public domain for the first time in India, addressing existing flagship Government of India policies, including but not limited to the Make in India initiative, Digital India initiative, Automotive Mission Plan, Nationally Determined Commitments under the Paris agreement, and the Atmanirbhar Bharat relief package. These studies have been designed to provide in-depth and lucid insights regarding choices for resource allocation by policymakers, thereby serving as a comprehensive guide for evidence-based policymaking in India.