A magnet delivery system (365, 365a, 465, 465a, 565, 665) for forming an anastomosis, the delivery system (365, 365a, 465, 465a, 565, 665) comprising: a wire guide (333, 433, 533, 633); a catheter (335, 435, 535, 635) having a delivery portion for advancement into a visceral space, the delivery portion having a first catheter lumen extending at least partially therethrough and slidably receiving the wire guide (333, 433, 533, 633), the delivery portion including a distal end (336, 536) of the catheter (335, 435, 535, 635); a strand (337, 437, 537, 637) connected to the catheter (335, 435, 535, 635), a distal end of the strand (337, 437, 537, 637) having a connector (338, 438, 540) slidably connected to the wire guide (333, 433, 533, 633), the connector (338, 438, 540) selectively detachable from the wire guide (333, 433, 533, 633); and a first magnet (330, 430, 530) defining a lumen therethrough, wherein the first magnet (330, 430, 530) includes an elongate jacket enclosing two magnetic members (431, 432) positioned along a longitudinal axis of the elongate jacket; characterized in that the first magnet (330, 430, 530) is detachably connected to the delivery portion of the catheter (335, 435, 535, 635) by disposing the first wire guide (333, 433, 533, 633) through the lumen of the first magnet (330, 430, 530) such that a proximal end of the first magnet (330, 430, 530) is positioned distal to the distal end (336, 536) of the catheter (335, 435, 535, 635), and disposing the strand (337, 437, 537, 637) alongside the first magnet (330, 430, 530) and connecting the connector (338, 438, 540) of the strand (337, 437, 537, 637) to the wire guide (333, 433, 533, 633) at a location distal to the proximal end of the first magnet (330, 430, 530); and the strand (337, 437, 637) is slidably connected to the catheter (335, 435, 635); or the strand is fixedly attached to the distal end of the catheter. a wire guide (333, 433, 533, 633); a catheter (335, 435, 535, 635) having a delivery portion for advancement into a visceral space, the delivery portion having a first catheter lumen extending at least partially therethrough and slidably receiving the wire guide (333, 433, 533, 633), the delivery portion including a distal end (336, 536) of the catheter (335, 435, 535, 635); a strand (337, 437, 537, 637) connected to the catheter (335, 435, 535, 635), a distal end of the strand (337, 437, 537, 637) having a connector (338, 438, 540) slidably connected to the wire guide (333, 433, 533, 633), the connector (338, 438, 540) selectively detachable from the wire guide (333, 433, 533, 633); and a first magnet (330, 430, 530) defining a lumen therethrough, wherein the first magnet (330, 430, 530) includes an elongate jacket enclosing two magnetic members (431, 432) positioned along a longitudinal axis of the elongate jacket; characterized in that the first magnet (330, 430, 530) is detachably connected to the delivery portion of the catheter (335, 435, 535, 635) by disposing the first wire guide (333, 433, 533, 633) through the lumen of the first magnet (330, 430, 530) such that a proximal end of the first magnet (330, 430, 530) is positioned distal to the distal end (336, 536) of the catheter (335, 435, 535, 635), and disposing the strand (337, 437, 537, 637) alongside the first magnet (330, 430, 530) and connecting the connector (338, 438, 540) of the strand (337, 437, 537, 637) to the wire guide (333, 433, 533, 633) at a location distal to the proximal end of the first magnet (330, 430, 530); and the strand (337, 437, 637) is slidably connected to the catheter (335, 435, 635); or the strand is fixedly attached to the distal end of the catheter.