An infusion set (101) includes a base (121), a flexible catheter (142) and an introducer needle (134). The flexible catheter (142) is movable from a first catheter position disposed substantially entirely within the base (121) to a second catheter position in which a free end of the flexible catheter (142) is disposed externally of the base (121). The introducer needle (134) is movable between a first introducer needle position disposed substantially entirely within the base (121) and a second introducer needle position in which a free end of the introducer needle (134) is disposed externally of the base (121). An activation button (161) is movable between first and second button positions. When the activation button (161) is moved from the first button position to the second button position, the flexible catheter (142) is moved from the first to the second catheter position, and the introducer needle (134) is moved from the first to the second introducer needle position to facilitate insertion of the catheter (142) and back to the first introducer needle position to store the introducer needle (134) within the base (121).