Moick S, Hiesmayr M, Mouhieddine M, et al. - This study was undertaken to present the strategy, methods, instruments, and experience of developing and implementing nutritionDay 2.0, an audit and feedback intervention that uses quality and economic indicators, feedback, benchmarking, and self-defined action strategies to reduce the KTA gap in hospital nutrition care. An evidence based multi-professional mixed-methods approach was applied to develop and implement nutritionDay 2.0. Researchers synthesized further evidence from the literature, online surveys, a pilot study, World Cafes and individual expert feedback involving international health care professionals, nutrition care scientists, and patients. The data revealed that nutritionDay 2.0 has the potential to promote behavioral and practice changes and improve hospital nutrition care outcomes in clinical practice. The findings created advances in understanding about institutional malnutrition and the quality of hospital nutrition care. The ongoing assessment of the initiative will reveal how far the KTA gap in hospital nutrition care was addressed and facilitate the knowledge of the mechanisms necessary for successful audit and feedback.