Auto-injector for administering a dose of a liquid medicament, comprising - a substantially cylindrical chassis arranged to contain a pre-filled syringe with a syringe barrel filled with the medicament, an injection needle and a stopper for sealing the syringe barrel, - a needle shroud slidably arranged within the chassis and adapted to rest on the skin of a patient receiving an injection, - a plunger adapted to translate the stopper to expel the dose of the medicament through the injection needle, - a coupling shroud slidably arranged within the chassis and releasably coupled to the plunger and - a drive means capable of, upon release, driving the coupling shroud from a first position in a proximal direction, wherein the proximal translatory movement of the coupling shroud with respect to the chassis - translates the pre-filled syringe in the proximal direction to expose the injection needle, - depresses the plunger connected to the stopper into the syringe barrel to expel the dose of medicament and - advances the needle shroud to a safe position to surround the injection needle after the injection, wherein the coupling shroud is arranged to be decoupled from the plunger at a second position, wherein a coupling catch (6.2) on the coupling shroud is arranged to abut against a shoulder (9.1) formed to the plunger to releasably couple the plunger to the coupling shroud, wherein a ramped engagement of the coupling catch (6.2) and the shoulder (9.1) is arranged so as to allow for a deflection of the coupling catch (6.2) in a radial outward direction on translating the coupling shroud with respect to the plunger in the proximal direction and wherein the coupling catch (6.2) abuts against the chassis in the radial outward direction so as to prevent a decoupling of the plunger and the coupling shroud until the second position is reached, wherein the second position is defined by an aperture (2.1) formed into the chassis, wherein the aperture (2.1) is arranged to allow the coupling catch (6.2) of the coupling shroud to be deflected in the radial outward direction to decouple the plunger from the coupling shroud, wherein the needle shroud is arranged to prevent the decoupling of plunger and coupling shroud when the needle shroud is in a retracted position, whereas the needle shroud is arranged to allow for the decoupling of plunger and coupling shroud when the needle shroud is moved from the retracted position towards the safe position. - a substantially cylindrical chassis arranged to contain a pre-filled syringe with a syringe barrel filled with the medicament, an injection needle and a stopper for sealing the syringe barrel, - a needle shroud slidably arranged within the chassis and adapted to rest on the skin of a patient receiving an injection, - a plunger adapted to translate the stopper to expel the dose of the medicament through the injection needle, - a coupling shroud slidably arranged within the chassis and releasably coupled to the plunger and - a drive means capable of, upon release, driving the coupling shroud from a first position in a proximal direction, wherein the proximal translatory movement of the coupling shroud with respect to the chassis - translates the pre-filled syringe in the proximal direction to expose the injection needle, - depresses the plunger connected to the stopper into the syringe barrel to expel the dose of medicament and - advances the needle shroud to a safe position to surround the injection needle after the injection, wherein the coupling shroud is arranged to be decoupled from the plunger at a second position, wherein a coupling catch (6.2) on the coupling shroud is arranged to abut against a shoulder (9.1) formed to the plunger to releasably couple the plunger to the coupling shroud, wherein a ramped engagement of the coupling catch (6.2) and the shoulder (9.1) is arranged so as to allow for a deflection of the coupling catch (6.2) in a radial outward direction on translating the coupling shroud with respect to the plunger in the proximal direction and wherein the coupling catch (6.2) abuts against the chassis in the radial outward direction so as to prevent a decoupling of the plunger and the coupling shroud until the second position is reached, wherein the second position is defined by an aperture (2.1) formed into the chassis, wherein the aperture (2.1) is arranged to allow the coupling catch (6.2) of the coupling shroud to be deflected in the radial outward direction to decouple the plunger from the coupling shroud, wherein the needle shroud is arranged to prevent the decoupling of plunger and coupling shroud when the needle shroud is in a retracted position, whereas the needle shroud is arranged to allow for the decoupling of plunger and coupling shroud when the needle shroud is moved from the retracted position towards the safe position. - translates the pre-filled syringe in the proximal direction to expose the injection needle, - depresses the plunger connected to the stopper into the syringe barrel to expel the dose of medicament and - advances the needle shroud to a safe position to surround the injection needle after the injection,