BACKGROUND: Interhospital transfer is an understudied area within transitions of care. The process by which hospitals accept and transfer patients is not well described. National trends and best practices are unclear. OBJECTIVE: To describe the demographics of large transfer centers, to identify common handoff practices, and to describe challenges and notable innovations involving the interhospital transfer handoff process. DESIGN AND PARTICIPANTS: A convenience sample of 32 tertiary care centers in the United States was studied. Respondents were typically transfer center directors surveyed by phone. MAIN MEASURES: Data regarding transfer center demographics, handoff communication practices, electronic infrastructure, and data sharing were obtained. RESULTS: The median number of patients transferred each month per receiving institution was 700 (range, 250-2500); on average, 28% of these patients were transferred to an intensive care unit. Transfer protocols and practices varied by institution. Transfer center coordinators typically had a medical background (78%), and critical care-trained registered nurse was the most prevalent (38%). Common practices included: mandatory recorded 3-way physician-to-physician conversation (84%) and mandatory clinical status updates prior to patient arrival (81%). However, the timeline of clinical status updates was variable. Less frequent transfer practices included: electronic medical record (EMR) cross-talk availability and utilization (23%), real-time transfer center documentation accessibility in the EMR (32%), and referring center clinical documentation available prior to transport (29%). A number of innovative strategies to address challenges involving interhospital handoffs are reported. CONCLUSIONS: Interhospital transfer practices vary widely amongst tertiary care centers. Practices that lead to improved patient handoffs and reduced medical errors need additional prospective evaluation.