A detachment system for delivering embolic coils to a treatment site in a vasculature of a patient, comprising: an elongated, flexible shape memory polymer tube having a longitudinal axis, a distal portion and a proximal portion, said elongated, flexible shape memory polymer tube having a tubular wall with an inner wall surface defining an interior lumen extending through the elongated, flexible shape memory polymer tube between the distal portion and the proximal portion of the elongated, flexible shape memory polymer tube, the distal portion of the elongated, flexible shape memory polymer tube having a permanent shape and a temporary shape; a therapeutic embolic coil releasably mounted to the distal portion of said elongated, flexible shape memory polymer tube, said embolic coil having a distal end and a proximal end; a headpiece having a distal portion and a proximal portion, the distal portion of the headpiece being attached to the proximal end of the embolic coil, and the proximal portion of the headpiece being releasably attached within said distal portion of said elongated, flexible shape memory polymer tube, said permanent shape having an enlarged diameter configuration with an inner diameter that is larger than an outer diameter of the headpiece; and a resistive heating element contained within the interior lumen of the distal portion of the flexible shape memory polymer tube, and disposed longitudinally along the inner wall surface of the tubular wall of the distal portion of the flexible shape memory polymer tube, and wherein said proximal portion of the headpiece is configured to be releasable from said distal portion of said elongated, flexible shape memory polymer tube by heating of said distal portion of the elongated, flexible shape memory polymer tube to cause said distal portion of the elongated, flexible shape memory polymer tube to change from said temporary shape having a reduced diameter configuration to said enlarged diameter configuration characterised in that the resistive heating element is disposed in immediate contact with the inner wall surface of the tubular wall of the distal portion of the flexible shape memory polymer tube. an elongated, flexible shape memory polymer tube having a longitudinal axis, a distal portion and a proximal portion, said elongated, flexible shape memory polymer tube having a tubular wall with an inner wall surface defining an interior lumen extending through the elongated, flexible shape memory polymer tube between the distal portion and the proximal portion of the elongated, flexible shape memory polymer tube, the distal portion of the elongated, flexible shape memory polymer tube having a permanent shape and a temporary shape; a therapeutic embolic coil releasably mounted to the distal portion of said elongated, flexible shape memory polymer tube, said embolic coil having a distal end and a proximal end; a headpiece having a distal portion and a proximal portion, the distal portion of the headpiece being attached to the proximal end of the embolic coil, and the proximal portion of the headpiece being releasably attached within said distal portion of said elongated, flexible shape memory polymer tube, said permanent shape having an enlarged diameter configuration with an inner diameter that is larger than an outer diameter of the headpiece; and a resistive heating element contained within the interior lumen of the distal portion of the flexible shape memory polymer tube, and disposed longitudinally along the inner wall surface of the tubular wall of the distal portion of the flexible shape memory polymer tube, and wherein said proximal portion of the headpiece is configured to be releasable from said distal portion of said elongated, flexible shape memory polymer tube by heating of said distal portion of the elongated, flexible shape memory polymer tube to cause said distal portion of the elongated, flexible shape memory polymer tube to change from said temporary shape having a reduced diameter configuration to said enlarged diameter configuration characterised in that the resistive heating element is disposed in immediate contact with the inner wall surface of the tubular wall of the distal portion of the flexible shape memory polymer tube.