This document provides an overview of the collaboration between multiple institutions to produce an assessment of the global livestock sector called "Livestock in a Changing Landscape". The assessment aims to take a comprehensive look at the drivers of change in the livestock sector, the environmental, social, and health consequences, and potential responses. It involves input from a diverse range of experts from different organizations and regions to reflect the heterogeneity of livestock production systems around the world. Challenges addressed in the assessment include balancing the livelihoods of millions who depend on livestock with environmental sustainability and equitable development as the sector continues to undergo rapid changes globally.