In 2013, over 6.3 million children worldwide died before their fifth birthday. Most of these children lived in developing countries and died of a disease or combination of diseases that could be easily prevented or treated. Undernutrition contributes close to one in two underchild deathsi. There is widespread consensus on the role the health sector plays for nutrition and agreement on the fact that maximizing the effectiveness means integrating nutrition-‐related actions into the health systems, health strategy and health budget of every country. However, implementation remains a challenge for many countries and further actions are required to identify optimal delivery models for malnutrition prevention, identification and treatment services, adapted to specific contexts. The capacity of health systems should be at the core of the debate for the sustainability and long-‐term success of the undernutrition response.