Abstract: A needle-fee injection device including: a housing having a striker channel, a dose chamber, and a jet orifice; a syringe plunger movable in the dose chamber between reload and ejection positions; a striker movable within the striker channel between the reload and ejection positions; a spring for storing energy to be delivered to the striker; a driven member; an engagement member movable between engagement and disengagement positions with the driven member such that engagement of the engagement member with the driven member causes the spring to store energy and disengagement of the engagement member with the driven member allows the stored energy in the spring to be delivered to the striker causing the striker to impact the syringe plunger and eject the medicament from the dose chamber through the jet orifice.