An injection device for delivering a dose of medicament from a syringe, the injection device comprising: a housing comprising a forward body and rearward body and wherein the forward body and rearward body are axially moveably interconnected; a drive mechanism arranged, in use, to deliver a dose from said syringe a trigger for activating the drive mechanism; and an interlock having a locked position in which activation of the drive mechanism by the trigger is prevented and an unlocked position in which the drive mechanism may be activated, the interlock being moved to the unlocked position by relative axial movement of the forward body and rearward body caused by the injection device being urged against an injection site; and characterised in that the injection device further comprises: an interlock hold arrangement comprising: an engagement feature in one of the rearward body or forward body; a cam surface, fixed relative to a forward facing skin abutment surface of the injection device, which moves into alignment with the engagement feature when the interlock is in the unlocked position; and a resilient member which is deflected by the cam surface so as to provide a holding engagement with the engagement feature; and configured to help maintain the axial position of the rearward body relative to the forward body when the interlock is in the unlocked position and the forward facing skin abutment surface is in contact with an injection site. a housing comprising a forward body and rearward body and wherein the forward body and rearward body are axially moveably interconnected; a drive mechanism arranged, in use, to deliver a dose from said syringe a trigger for activating the drive mechanism; and an interlock having a locked position in which activation of the drive mechanism by the trigger is prevented and an unlocked position in which the drive mechanism may be activated, the interlock being moved to the unlocked position by relative axial movement of the forward body and rearward body caused by the injection device being urged against an injection site; and characterised in that the injection device further comprises: an interlock hold arrangement comprising: an engagement feature in one of the rearward body or forward body; a cam surface, fixed relative to a forward facing skin abutment surface of the injection device, which moves into alignment with the engagement feature when the interlock is in the unlocked position; and a resilient member which is deflected by the cam surface so as to provide a holding engagement with the engagement feature; and configured to help maintain the axial position of the rearward body relative to the forward body when the interlock is in the unlocked position and the forward facing skin abutment surface is in contact with an injection site. an engagement feature in one of the rearward body or forward body; a cam surface, fixed relative to a forward facing skin abutment surface of the injection device, which moves into alignment with the engagement feature when the interlock is in the unlocked position; and a resilient member which is deflected by the cam surface so as to provide a holding engagement with the engagement feature; and configured to help maintain the axial position of the rearward body relative to the forward body when the interlock is in the unlocked position and the forward facing skin abutment surface is in contact with an injection site.