A payload ejection system for hosting and controllably ejecting a payload from a host spacecraft , comprising: a payload ejection mechanism attachable to the host spacecraft , said payload ejection mechanism including a base plate attachable to said host spacecraft and a payload release plate ; a payload assembly releasibly attached to said payload release plate , a payload being attachable to said payload assembly ; and said payload ejection mechanism characterized in that said payload ejection mechanism includes at least two deployment hinge assemblies , each including two hinge plates hinged together, wherein one of the two hinge plates is hinged to said base plate and the other of the two hinge plates is hinged to said payload release plate , wherein at least one of the deployment hinge assemblies has hinge axes that are non-parallel to those of at least one other of the deployment hinge assemblies so that the payload release plate can only propagate parallel to the base plate , wherein, when said payload ejection mechanism is activated, the one of the two hinge plates hinges with respect to the base plate and the other of the two hinge plates hinges with respect to the payload release plate to drive the payload assembly away from the host spacecraft along an ejection axis to eject the payload assembly away from the host spacecraft with forces acting upon the payload assembly being substantially equal across the interface between the payload assembly and the payload release plate at a moment of release of the payload assembly from said payload ejection mechanism by maintaining controlled contact during the ejection such that the payload has no angular momentum transverse to the ejection axis or linear momentum transverse to the ejection axis at the time of release regardless of a location of the payload center of mass of the payload with respect to a geometric center of said payload ejection mechanism to eject said payload assembly away from said host spacecraft with a negligible tumble rate. a payload ejection mechanism attachable to the host spacecraft , said payload ejection mechanism including a base plate attachable to said host spacecraft and a payload release plate ; a payload assembly releasibly attached to said payload release plate , a payload being attachable to said payload assembly ; and said payload ejection mechanism characterized in that said payload ejection mechanism includes at least two deployment hinge assemblies , each including two hinge plates hinged together, wherein one of the two hinge plates is hinged to said base plate and the other of the two hinge plates is hinged to said payload release plate , wherein at least one of the deployment hinge assemblies has hinge axes that are non-parallel to those of at least one other of the deployment hinge assemblies so that the payload release plate can only propagate parallel to the base plate , wherein, when said payload ejection mechanism is activated, the one of the two hinge plates hinges with respect to the base plate and the other of the two hinge plates hinges with respect to the payload release plate to drive the payload assembly away from the host spacecraft along an ejection axis to eject the payload assembly away from the host spacecraft with forces acting upon the payload assembly being substantially equal across the interface between the payload assembly and the payload release plate at a moment of release of the payload assembly from said payload ejection mechanism by maintaining controlled contact during the ejection such that the payload has no angular momentum transverse to the ejection axis or linear momentum transverse to the ejection axis at the time of release regardless of a location of the payload center of mass of the payload with respect to a geometric center of said payload ejection mechanism to eject said payload assembly away from said host spacecraft with a negligible tumble rate. <EOS>