A delivery system assembly facilitating deployment of an implantable medical device, the assembly comprising: a handle including a first control member and a second control member; an elongate core extending from a proximal end thereof to a flared distal end thereof, the proximal end being fixed within the handle, and the flared distal end being configured to conform to a proximal end of the medical device; an elongate outer tube forming a lumen in which the core extends, the outer tube including a proximal end, a distal end and a distal-most portion extending proximally from the distal end of the outer tube, the lumen having a proximal opening at the proximal end of the outer tube and a distal opening at the distal end of the outer tube, the proximal end of the outer tube being coupled to the first control member of the handle, the outer tube being longitudinally moveable, with respect to the handle and the core, between first and second positions, by means of the first control member, the flared distal end of the core being located within the distal-most portion of the outer tube, when the outer tube is in the first position, and the lumen of the outer tube, along a length of the distal-most portion, being sized to contain both the flared distal end of the core and an entirety of the medical device, together, within the distal-most portion, when the outer tube is in the first position; an elongate pull-wire extending along the core and within the lumen of the outer tube, the pull-wire including a proximal end and a distal end, the proximal end of the pull-wire being coupled to the second control member of the handle and the distal end of the pull-wire being anchored to the core in close proximity to the flared distal end thereof; and a sheath extending around the pull-wire and the core and within the lumen of the outer tube, the sheath including a distal end, a proximal end and a slot opening located therebetween, the distal end of the sheath being coupled to the core in close proximity to the anchored distal end of the pull-wire, the proximal end of the sheath being located within the lumen of the outer tube and spaced apart, distally, from the handle, and the slot opening being located and sized to allow the pull-wire to pass laterally therethrough; wherein, when the outer tube is in the second position, the flared distal end of the core is located in proximity to the distal end of the outer tube; and wherein the distal-most portion of the outer tube is larger in diameter than the portion of the outer tube proximal of the distal-most portion. a handle including a first control member and a second control member; an elongate core extending from a proximal end thereof to a flared distal end thereof, the proximal end being fixed within the handle, and the flared distal end being configured to conform to a proximal end of the medical device; an elongate outer tube forming a lumen in which the core extends, the outer tube including a proximal end, a distal end and a distal-most portion extending proximally from the distal end of the outer tube, the lumen having a proximal opening at the proximal end of the outer tube and a distal opening at the distal end of the outer tube, the proximal end of the outer tube being coupled to the first control member of the handle, the outer tube being longitudinally moveable, with respect to the handle and the core, between first and second positions, by means of the first control member, the flared distal end of the core being located within the distal-most portion of the outer tube, when the outer tube is in the first position, and the lumen of the outer tube, along a length of the distal-most portion, being sized to contain both the flared distal end of the core and an entirety of the medical device, together, within the distal-most portion, when the outer tube is in the first position; an elongate pull-wire extending along the core and within the lumen of the outer tube, the pull-wire including a proximal end and a distal end, the proximal end of the pull-wire being coupled to the second control member of the handle and the distal end of the pull-wire being anchored to the core in close proximity to the flared distal end thereof; and a sheath extending around the pull-wire and the core and within the lumen of the outer tube, the sheath including a distal end, a proximal end and a slot opening located therebetween, the distal end of the sheath being coupled to the core in close proximity to the anchored distal end of the pull-wire, the proximal end of the sheath being located within the lumen of the outer tube and spaced apart, distally, from the handle, and the slot opening being located and sized to allow the pull-wire to pass laterally therethrough; wherein, when the outer tube is in the second position, the flared distal end of the core is located in proximity to the distal end of the outer tube; and wherein the distal-most portion of the outer tube is larger in diameter than the portion of the outer tube proximal of the distal-most portion.