Food insecurity and poor nutritional status remain widespread problems in the Horn of Africa (HOA). A multi-pronged nutrition-sensitive approach to development has been shown to be the best route for sustained reductions in undernutrition. This approach requires effective coordination. This policy brief articulates the commitment of the HOA states to rapidly scale up comprehensive nutrition services across and within the countries. It also identifies the role parliamentarians, policy-makers and politicians can play in supporting this rapid scale-up and roll-out of Food and Nutrition Security (FNS) services aimed at strengthening FNS coordination.