The Global Alliance for Improved Nutrition (GAIN) and Wellspring Development designed and hosted a series of in-person and online consultations with partners of the Dutch Ministry of Foreign Affairs to examine challenges in improving the quality of diets of population groups living in rural areas of low- and lower-middle-income countries. These groups largely consume nutrient-inadequate, even unhealthy, diets and face heavy burdens of malnutrition. This first paper, out of six, looks specifically at the challenges of setting targets for dietary quality improvement. The aim of the discussions was to gather examples of successful project interventions at scale, to understand the decision processes of different organisations, and to identify important points of convergence in conceptualisation and action.