Individuals living with serious mental illness (SMI) have increased mortality chiefly because of a higher prevalence of chronic disorders, including some cancers and infectious diseases. Although increased prevalence of these disorders may be attributable to lifestyle and risk behaviors, there is evidence that they may not be appropriately addressed by health professionals. We conducted a review of the literature describing preventive services for cancer and infectious diseases provided to individuals with SMI. Most studies demonstrated a 20%–30% reduced likelihood of breast, cervical, and colorectal cancer screening, or immunizations for influenza and pneumonia, in patients with SMI compared with those without SMI. This is most common in those with the most severe forms of SMI. HIV and hepatitis were more commonly screened for in people with SMI than the general population, likely because of the increased risk for these disorders within this group, but there were still substantial proportions of individuals with SMI who had never received a screening, or had not received a recent screening, for these disorders. The mental health nursing profession has an opportunity to address the disparity in care for cancer and infectious diseases, as well as other physical disorders, experienced by mental health consumers. With systemic support and ongoing education, mental health nurses may be capable of conducting or recommending screening for disorders and providing lifestyle advice. These practices may help to reduce the increased prevalence of chronic disease in SMI populations.