The present invention is directed to a holder for use in positioning a pulse oximeter sensor in multiple selectable locations relative to a patient's extremities. The holder includes at least one flexible elongate member that is conformable to and, preferably, about a patient's extremity. A connector on the elongate member is utilized to secure the elongate member to the patient's extremity. Additionally, the elongate member's inside surface contains one or more recesses for selectively receiving a sensor and holding that sensor relative to one or more positions on the inside surface of the flexible sensor holder. The inclusion of multiple recesses allows medical personnel flexibility in positioning a medical sensor. In one embodiment, the holder includes two elongate members for conforming about two portions of a patient's extremity to reduce movement between the extremity and a sensor held by the sensor holder.