Background: Hyperglycaemia is prevalent in critically ill patients and can increase mortality. This report presents and validates a glycaemic control system using a physiologically based metabolic control model (Glucosafe) and an associated integral based parameter identification method. The intended application for this glycaemic control system, and the associated model and parameter identification method is glycaemic control of critically ill patients. Methods: The glycaemic control system uses the Glucosafe glucose-insulin metabolic model. Time varying insulin sensivity, SI , is determined between measurements using an integral-based method. The glycaemic control system is validated by its ability to keep patients in a normoglycaemic range (4.4-7.75 mmol/L). Clinical control interventions are determined by optimization over a series of penalty functions. The system is validated against 20 virtual patients by using patient specific insulin sensivity profiles based on clinical data from 20 critical care patients at Christchurch Hospital (New Zealand). Results: The overall median blood glucose concentration for all 20 patients is 6.05 mmol/L, and the IQR is 5.54-6.62 mmol/L. The overall number of hypoglycaemic measurements per patient is 0 (blood glucose measurements below 2.2 mmol/L). The overall mean percent of measurements inside the normoglycaemic range (4.4-7.75 mmol/L) is 87.7 %. Conclusions: The results for the glycaemic control validation presented are comparable to other similar studies by Chase et al. (2008) and are acceptable for later use in clinical pilot trials.