An injection device (110) is described having a housing (112) and a cap (130). The injection device (110) houses a syringe (114) having a needle which is sealed by a boot (118). The cap (130) is arranged so that the boot (118) can be connected to the cap (130) whilst exerting a minimal force on the syringe, but cannot be removed from the cap (130) without applying a significantly greater force to the syringe. The housing (112) and cap (130) are arranged so that upon removal of the cap (130) from the housing (112), the boot (118) is removed from the syringe (114).
