Auto-injector for administering a dose of a liquid medicament, comprising: - an elongate housing arranged to contain a syringe with a hollow needle and a stopper for sealing the syringe and displacing the medicament, the housing having a distal end and a proximal end with an orifice intended to be applied against an injection site, wherein the syringe is slidably arranged with respect to the housing, - spring means capable of, upon activation: - pushing the needle from a covered position inside the housing into an advanced position through the orifice and past the proximal end, - operating the syringe to supply the dose of medicament, and - retracting the syringe with the needle into the covered position after delivering the medicament, - activating means arranged to lock the spring means in a pressurized state prior to manual operation and capable of, upon manual operation, releasing the spring means for injection, wherein the spring means is a single compression spring arranged to be grounded at a distal end (8.1) in the housing for advancing the needle and for injecting the dose of medicament via a plunger and wherein the compression spring is arranged to have its ground in the housing switched to its proximal end (8.2) while the distal end (8.1) of the compression spring is released from its ground in the housing for retracting the syringe, characterized in that a retraction sleeve is axially movable arranged in the housing, wherein at least one latch is provided for axially fixing the retraction sleeve in a maximum proximal position, wherein the compression spring is arranged inside the retraction sleeve with its distal end bearing against a distal end face and with its proximal end bearing against a thrust face of a decoupling member, wherein the decoupling member is arranged to decouple the latch when being moved in proximal direction nearly into a maximum proximal position, thus allowing the retraction sleeve to move in distal direction and retract the needle, wherein at least two resilient decoupling arms are arranged at the decoupling member, the decoupling arms having inner ramped surfaces bearing against a first shoulder of the plunger in proximal direction, wherein the resilient decoupling arms are supportable by an inner wall of the retraction sleeve in order to prevent the decoupling arms from being flexed outward and slip past the first shoulder and wherein at least one aperture is arranged in the retraction sleeve allowing the decoupling arms to be flexed outward by the first shoulder thus allowing the first shoulder to slip through the decoupling arms in proximal direction, wherein the plunger is arranged for pushing the syringe and/or the stopper in proximal direction. - an elongate housing arranged to contain a syringe with a hollow needle and a stopper for sealing the syringe and displacing the medicament, the housing having a distal end and a proximal end with an orifice intended to be applied against an injection site, wherein the syringe is slidably arranged with respect to the housing, - spring means capable of, upon activation: - pushing the needle from a covered position inside the housing into an advanced position through the orifice and past the proximal end, - operating the syringe to supply the dose of medicament, and - retracting the syringe with the needle into the covered position after delivering the medicament, - pushing the needle from a covered position inside the housing into an advanced position through the orifice and past the proximal end, - operating the syringe to supply the dose of medicament, and - retracting the syringe with the needle into the covered position after delivering the medicament, - activating means arranged to lock the spring means in a pressurized state prior to manual operation and capable of, upon manual operation, releasing the spring means for injection,