The present invention provides apparatuses, systems, methods and kits for fastening sutures or similar devices used in medical surgical procedures. In particular, the present invention is suitable for use with percutaneous or minimally invasive procedures in which sutures are placed with catheter-based devices wherein the tying of knots is particularly challenging. Suture fasteners of the present invention provide for fastening the sutures together in a fixed position at any location along the suture strands. In addition, the fasteners are adjustable to allow repositioning of the fastener after placement to a new desired location along the suture strands. Similarly, such fasteners may be used to hold a single suture strand for various applications.