BACKGROUND: Retention in care for human immunodeficiency virus (HIV)-infected patients is a National HIV/AIDS Strategy priority. We hypothesized that retention could be improved with coordinated messages to encourage patients' clinic attendance. We report here the results of the first phase of the Centers for Disease Control and Prevention/Health Resources and Services Administration Retention in Care project. METHODS: Six HIV-specialty clinics participated in a cross-sectionally sampled pretest-posttest evaluation of brochures, posters, and messages that conveyed the importance of regular clinic attendance. 10,018 patients in 2008-2009 (preintervention period) and 11,039 patients in 2009-2010 (intervention period) were followed up for clinic attendance. Outcome variables were the percentage of patients who kept 2 consecutive primary care visits and the mean proportion of all primary care visits kept. Stratification variables were: new, reengaging, and active patients, HIV RNA viral load, CD4 cell count, age, sex, race or ethnicity, risk group, number of scheduled visits, and clinic site. Data were analyzed by multivariable log-binomial and linear models using generalized estimation equation methods. RESULTS: Clinic attendance for primary care was significantly higher in the intervention versus preintervention year. Overall relative improvement was 7.0% for keeping 2 consecutive visits and 3.0% for the mean proportion of all visits kept (P < .0001). Larger relative improvement for both outcomes was observed for new or reengaging patients, young patients and patients with elevated viral loads. Improved attendance among the new or reengaging patients was consistent across the 6 clinics, and less consistent across clinics for active patients. CONCLUSION: Targeted messages on staying in care, which were delivered at minimal effort and cost, improved clinic attendance, especially for new or reengaging patients, young patients, and those with elevated viral loads.