This guideline covers identifying and caring for adults who are malnourished or at risk of malnutrition in hospital or in their own home or a care home. It offers advice on how oral, enteral tube feeding and parenteral nutrition support should be started, administered and stopped. It aims to support healthcare professionals identify malnourished people and help them to choose the most appropriate form of support. In August 2017, we updated the links in the footnotes to recommendations 1.3.4 and 1.8.15. Recommendation 1.7.17 was also updated and links added to National Patient Safety Agency documents.