A stent delivery device, comprising: a handle assembly, an elongate inner member extending distally from the handle assembly along a longitudinal axis, the inner member having a proximal end and a distal end; an elongate outer tubular member extending distally from the handle assembly along the longitudinal axis about the elongate inner member, the outer tubular member having a proximal end and a distal end; the handle assembly including: a handle fixedly secured to the inner member; an actuator fixedly secured to the outer tubular member, wherein actuation of the actuator relative to the handle between a first position and a second position causes axial movement of the outer tubular member relative to the inner member; and a locking mechanism (40, 152, 252) for restricting actuation of the actuator from the first position to the second position, the locking mechanism having a locked position and an unlocked position; wherein in the locked position the actuator is prevented from moving from the first position to the second position and in the unlocked position the actuator is permitted to move from the first position to the second position, wherein the locking mechanism includes a protrusion on one of the handle and the actuator, the protrusion positioned in a channel formed in the other of the handle and the actuator, wherein the channel includes a circumferential portion and a longitudinal portion, wherein the protrusion travels circumferentially in the circumferential portion of the channel into longitudinal alignment with the longitudinal portion when the locking mechanism is moved from the locked position to the unlocked position, and the protrusion travels longitudinally in the longitudinal portion of the channel when the actuator is moved to the second position. a handle assembly, an elongate inner member extending distally from the handle assembly along a longitudinal axis, the inner member having a proximal end and a distal end; an elongate outer tubular member extending distally from the handle assembly along the longitudinal axis about the elongate inner member, the outer tubular member having a proximal end and a distal end; the handle assembly including: a handle fixedly secured to the inner member; an actuator fixedly secured to the outer tubular member, wherein actuation of the actuator relative to the handle between a first position and a second position causes axial movement of the outer tubular member relative to the inner member; and a locking mechanism (40, 152, 252) for restricting actuation of the actuator from the first position to the second position, the locking mechanism having a locked position and an unlocked position; wherein in the locked position the actuator is prevented from moving from the first position to the second position and in the unlocked position the actuator is permitted to move from the first position to the second position, wherein the locking mechanism includes a protrusion on one of the handle and the actuator, the protrusion positioned in a channel formed in the other of the handle and the actuator, a handle fixedly secured to the inner member; an actuator fixedly secured to the outer tubular member, wherein actuation of the actuator relative to the handle between a first position and a second position causes axial movement of the outer tubular member relative to the inner member; and a locking mechanism (40, 152, 252) for restricting actuation of the actuator from the first position to the second position, the locking mechanism having a locked position and an unlocked position; wherein in the locked position the actuator is prevented from moving from the first position to the second position and in the unlocked position the actuator is permitted to move from the first position to the second position, wherein the channel includes a circumferential portion and a longitudinal portion, wherein the protrusion travels circumferentially in the circumferential portion of the channel into longitudinal alignment with the longitudinal portion when the locking mechanism is moved from the locked position to the unlocked position, and the protrusion travels longitudinally in the longitudinal portion of the channel when the actuator is moved to the second position.