Objectives. We designed and evaluated interventions to increase adult immunizations within inner-city health centers. Methods. Interventions included reminders, standing orders, and walk-in “flu shot clinics.” Patients were surveyed and records evaluated. Results. Records from 1 center showed that immunization rates increased from 24% to 30% (P<.001) for patients aged 50 to 64 years and from 45% to 53% for patients aged 65 years and older (P<.001). Self-reported vaccination rates did not increase. In logistic regression analyses, the strongest predictor of vaccination among patients aged 50 to 64 years was the belief that unvaccinated persons will contract influenza (odds ratio [OR]=5.4; 95% confidence interval [CI]=2.4, 12.0). Among patients aged 65 years and older, the strongest predictor of vaccination was the belief that friends/relatives thought that they should be vaccinated (OR=9.7; 95% CI=4.2, 22.3). Conclusions. Tailored interventions can improve immunization rates at inner-city health centers