United Nations Environment Programme is pleased to provide new Guidelines for Conducting Integrated Environmental Assessments. With the leadership of the Assessment Methodologies, Data and Information Group under the Global Environment Outlook, the participation of several of its members in the drafting and review process as well as a core group of authors, these Guidelines are now available for application by Integrated Environmental Assessment Practitioners and for consultation by the Integrated Environmental Assessment user community. This document is the result of United Nations Environment Programme Member State requests in both Governing Council and the United Nations Environment Assembly and is meant to provide guidance for a wide range of different types of Integrated Environmental Assessments. These can range from global to regional to rapid response assessments and emerging issues assessments. The Guidelines should be considered a ‘living document’ since they will be used and improved throughout the sixth Global Environment Outlook process as well as other on‐going assessment processes.