People with serious mental illness (SMI) are at increased risk of being infected by coronavirus disease 2019 (COVID-19) and have higher subsequent rates of hospitalization, morbidity, and mortality. 1,2 Factors that contribute to worse outcomes include concomitant medications, poorer premorbid general health, physical comorbidity, reduced access to medical care, and environmental and lifestyle factors such as lower socioeconomic status, overcrowding, smoking, or obesity. In light of these vulnerabilities, it is important that people with SMI are a priority group to receive a vaccination, should one be developed and deemed safe and effective. 3 De Hert and colleagues 3 noted that there is an ethical duty to prioritize vaccination for people with SMI given their increased risk of worse outcomes following COVID-19 infection and the structural barriers faced by people with SMI in accessing a vaccine. In addressing the Framework for Equitable Allocation of the COVID-19 Vaccine 4 principle mitigation of health inequities, people with SMI should be included with other priority groups, including Indigenous people, older adults, and people with physical health comorbidities.Over and above the ethical need to ensure vaccination allocation priority for people with SMI, evidence from existing vaccination programs suggests that there are challenges in achieving this aim at both an individual and public health level. People with SMI are less likely to receive preventive or guideline-appropriate health care for concerns such as cardiovascular disease and cancer. This reduced access to preventive care is reflected in the low uptake of immunizations recommended for adults among people with SMI. Of these, influenza may serve as a particularly useful model given the recommendation for an annual vaccination. In contrast with other vulnerable groups in the United States, influenza vaccination rates among people with SMI are as low as 25%. 5,6 Based on the experience with influenza vaccination programs, we have outlined key barriers and solutions to access any potential COVID-19 vaccine for people with SMI (Table ).