In order to anchor a suture in tissue, a device is proposed which has a guide sleeve, a sonotrode, an anchor, and the suture. The guide sleeve comprises a distal part having a smaller cross-section and a proximal part having a larger cross-section. The sonotrode extends in the lumen of the guide sleeve and comprises a distal end and a proximal end, wherein the proximal end is equipped for coupling the sonotrode to a vibration source (such as an ultrasonic device). The anchor is disposed at the distal end of the device and comprises an anchor base and an anchoring sleeve that rests on a shoulder of the anchor base. The anchoring sleeve has a material that can be liquefied by mechanical vibrations, or is made thereof. A central region of the suture runs through the anchor base, and two end regions of the suture are fastened to the guide sleeve. The anchoring sleeve is clamped, or disposed such that it can be clamped, between the anchor base and an impact sleeve, or the sonotrode, or the guide sleeve. The device is particularly suited for anchoring sutures in bone tissue.
