Entering the peritoneal cavity with the echoendoscope has been avoided because this endoscope is rather rigid and difficult to handle and maneuver in a limited space. Endoscopic ultrasound may be of help, however, to guide natural orifice translumenal endoscopic surgery (NOTES) procedures. This article provides an overview of the potential benefit and the few endoscopic ultrasound–based natural NOTES procedures performed to date.