This study tested the hypothesis that increasing the intensity of outpatient care for patients discharged from the hospital could lower their subsequent inpatient and total health-care costs. At discharge, 1,001 patients were stratified by risk of readmission (low, medium, or high) and randomly assigned to the intervention or control group. Discharge information (summaries, medications, and postdischarge needs) was provided to outpatient nurses who monitored intervention patients closely and attempted to resolve their problems. Intervention patients also received appointment reminders, and missed visits were promptly rescheduled. The cost of the intervention was $5.20 per patient per month. High-risk patients in the intervention group had significantly higher outpatient costs ($131/month vs. $107/month;P=0.02), but lower inpatient costs ($535/month vs. $800/month;P=0.02) than high-risk patients in the control group. Reduced inpatient costs in the high-risk intervention group were attributed to shorter, less intensive hospital stays. In conclusion, increasing ambulatory care resources after hospital discharge for high-risk patients may reduce health-care costs associated with readmission to the hospital.