A delivery system for a relatively compact implantable medical device , the system comprising an elongate inner shaft , an elongate outer shaft in sliding engagement around the inner shaft, and a proximal port , the inner shaft including a first lumen and a second lumen , both lumens extending longitudinally along a length of the inner shaft from proximal openings thereof to distal openings thereof, one or both of the proximal openings being in fluid communication with the proximal port, the distal openings being located at a distal end of the inner shaft, and the outer shaft including a distal-most portion sized to contain the medical device therein; and wherein the system comprises: an elongate tool extending within the first lumen of the inner shaft and being in sliding engagement therein, the tool including a proximal end accessible in proximity to the proximal port, and a distal end protruding from the distal end of the inner shaft, the distal end of the tool including a coupling feature ; and characterised by an elongate tethering member including a first end , a second end , a first segment , a second segment , and a retainer , the first segment extending within the second lumen of the inner shaft, from the first end to the second segment, the second segment extending from the first segment to the second end, and distally from the distal end of the inner shaft, the first end protruding from the proximal port and being joined to the retainer, and the second segment being configured to engage with a holding member of the medical device; and wherein the coupling feature of the tool is configured to couple with the second segment of the tethering member and to transfer a pull force thereto, when the pull force is applied to the proximal end of the tool, the pull force configured to draw the coupled second segment of the tethering member into the first lumen of the inner shaft, through the distal opening thereof. an elongate tool extending within the first lumen of the inner shaft and being in sliding engagement therein, the tool including a proximal end accessible in proximity to the proximal port, and a distal end protruding from the distal end of the inner shaft, the distal end of the tool including a coupling feature ; and characterised by an elongate tethering member including a first end , a second end , a first segment , a second segment , and a retainer , the first segment extending within the second lumen of the inner shaft, from the first end to the second segment, the second segment extending from the first segment to the second end, and distally from the distal end of the inner shaft, the first end protruding from the proximal port and being joined to the retainer, and the second segment being configured to engage with a holding member of the medical device; and wherein the coupling feature of the tool is configured to couple with the second segment of the tethering member and to transfer a pull force thereto, when the pull force is applied to the proximal end of the tool, the pull force configured to draw the coupled second segment of the tethering member into the first lumen of the inner shaft, through the distal opening thereof. <EOS>