Stunting affects 165 million children under 5 years of age around the world, and it can trap those children in a vicious cycle of poverty and undernutrition. Yet, key interventions when delivered during a critical 1,000-day window - during the mother's pregnancy and before a child turns 2 can lead to a reduced prevalence of stunting. This report showcases new developments in nutrition programmes and analyses progress towards reducing undernutrition. It also includes case studies from countries where nutrition has been improved at scale