Abstract The Joint British Diabetes Societies guidelines for the management of diabetic ketoacidosis (these do not cover Hyperosmolar Hyperglycaemic Syndrome) are available in full at:(i) http://www. diabetes. org. uk/About us/Our Views/Care recommendations/The-Management-of-Diabetic-Ketoacidosis-in-Adults;(ii) http://www. diabetes. nhs. uk/publications and resources/reports and guidance;(iii) http://www. diabetologists-abcd. org. uk/JBDS DKA Management. pdf. This article summarizes the main changes from previous guidelines and discusses the rationale for the new recommendations. The key points are: Monitoring of the response to treatment (i) The method of choice for monitoring the response to treatment is bedside measurement of capillary blood ketones using a ketone meter.(ii) If blood ketone measurement is not available, venous pH and bicarbonate should be used in conjunction with bedside blood glucose monitoring to assess treatment response.(iii) Venous blood should be used rather than arterial (unless respiratory problems dictate otherwise) in blood gas analysers.(iv) Intermittent laboratory confirmation of pH, bicarbonate and electrolytes only. Insulin administration (i) Insulin should be infused intravenously at a weight-based fixed rate until the ketosis has resolved.(ii) When the blood glucose falls below 14 mmol⁄ l, 10% glucose should be added to allow the fixed-rate insulin to be continued.(iii) If already taking, long-acting insulin analogues such as insulin glargine (Lantus, Sanofi Aventis, Guildford, Surry, UK) or insulin detemir (Levemir, Novo Nordisk, Crawley, West Sussex, UK.) should be continued in usual doses. Delivery of care (i) The diabetes specialist team should be involved as soon as possible.(ii) Patients should be nursed in areas where staff are experienced in the management of ketoacidosis.