The prevalence of metabolic syndrome is increased 2-3-fold in people with serious mental illness (SMI). Monitoring of physical health in these individuals is poor, despite clear guidance from the National Institute of Health and Clinical Excellence. The aim of this study was to assess the proportion of people with SMI who had been screened for metabolic abnormalities within the previous year and in a further study to assess the prevalence of undiagnosed metabolic abnormalities in people who had not been screened. The notes and computer records of 100 patients with SMI from community and in-patient settings were evaluated. In a subsequent study, the prevalence of metabolic syndrome was assessed in 71 previously unscreened patients. The study was carried out at the psychiatric in-patient and out-patient units in Southampton and Winchester. The frequency of screening and prevalence of the metabolic syndrome as defined by the International Diabetes Federation (IDF) were assessed. There was documented evidence that the following cardiovascular risk factors had been measured in the previous year: blood pressure (32%), glucose (16%), lipids (9%) and weight (2%). In the metabolic abnormalities study, 41 of 71 (58%) patients were found to fulfil the IDF criteria for the metabolic syndrome. Two had previously undiagnosed diabetes. Twelve percent of patients had a greater than 20% risk of a cardiovascular event within the next 10 years. Despite clear guidance and a high prevalence of undiagnosed metabolic syndrome, screening rates for metabolic abnormalities in people with SMI remain low. Improved screening of metabolic complications should lead to better identification and treatment of this clinical problem.