To test whether an intervention designed to encourage older patients and their caregivers to assert a more active role during care transitions can reduce rehospitalization rates. Quasi-experimental design whereby subjects receiving the intervention (n=158) were compared with control subjects derived from administrative data (n=1,235). A large integrated delivery system in Colorado. Community-dwelling adults aged 65 and older admitted to the study hospital with one of nine selected conditions. Intervention subjects received tools to promote cross-site communication, encouragement to take a more active role in their care and assert their preferences, and continuity across settings and guidance from a transition coach. Rates of postdischarge hospital use at 30, 60, and 90 days. Intervention subjects' care experience was assessed using the care transitions measure. The adjusted odds ratio comparing rehospitalization of intervention subjects with that of controls was 0.52 (95% confidence interval (CI)=0.28-0.96) at 30 days, 0.43 (95% CI=0.25-0.72) at 90 days, and 0.57 (95% CI=0.36-0.92) at 180 days. Intervention patients reported high levels of confidence in obtaining essential information for managing their condition, communicating with members of the healthcare team, and understanding their medication regimen. Supporting patients and caregivers to take a more active role during care transitions appears promising for reducing rates of subsequent hospitalization. Further testing may include more diverse populations and patients at risk for transitions who are not acutely ill.