The period following discharge from the hospital is a vulnerable time for patients. About half of adults experience a medical error after hospital discharge, and 19%–23% suffer an adverse event, most commonly an adverse drug event. This article reviews several important challenges to providing high-quality care as patients leave the hospital. These include the discontinuity between hospitalists and primary care physicians, changes to the medication regimen, new self-care responsibilities that may stress available resources, and complex discharge instructions. We also discuss approaches to promoting more effective transitions of care, including improvements in communication between inpatient and outpatient physicians, effective reconciliation of prescribed medication regimens, adequate education of patients about medication use, closer medical follow-up, engagement with social support systems, and greater clarity in physician–patient communication. By understanding the key challenges and adopting strategies to improve patient care in the transition from hospital to home, hospitalists could significantly reduce medical errors in the postdischarge period. Journal of Hospital Medicine 2007;2:314–323. © 2007 Society of Hospital Medicine.