In July 2017, HMS launched a Midline Use Initiative. This initiative was launched at the request of HMS member hospitals because several noticed significant use of midlines at their hospitals as they were doing quality work related to peripherally inserted central catheters (PICCs). A midline catheter is a vascular access device where the tip stops near the shoulder (unlike a PICC where the tip lies near the heart). Midlines are often used as substitutes for PICCs, but limited data is available on the use of midlines and associated complications. HMS is uniquely positioned to collect data and assess midline use across member hospitals. Through the work of this initiative, complications rates will be ascertained and compared with other vascular access devices.