Objective: To present a systematic review of the evaluation of randomized interventions directed toward improving somatic health for patients with severe mental illness (SMI). Method: A systematic search in PubMed, Embase, Cinahl, and PsycInfo was performed. The scope of the search was prospective studies for patients aged 18-70, published from January 2000 till June 2011. Randomized interventions directed toward improving somatic health for patients with SMI were selected. We excluded studies on elderly, children, and studies performed before 2000. Information on population, type of intervention, follow-up, outcome measures, and on authors' conclusions were drawn from the original articles. Results: Twenty-two original studies were included, presenting four types of interventions: health education (n = 9), exercise (n = 6), smoking cessation (n = 5), and changes in health care organization (n = 2). To evaluate the effect of these studies 93 different outcome measures were used in 16 categories. Conclusion: Many interventions directed toward improving somatic health for patients with SMI have been started. These studies did not apply similar evaluations, and did not use uniform outcome measures of the effect of their interventions. Valuable comparisons on effectiveness are therefore almost impossible. © 2013 John Wiley & Sons A/S.