Generalized Killing tensors are defined and the integrability conditions discussed to show that the familiar result that a space of constant curvature admits the maximum number of Killing vectors and second order Killing tensors does not necessarily generalize. The existence of second order Generalized Killing Yano tensors in spherically symmetric static space-times is investigated and a non-redundant example is given. It is proved that the natural vector analogue of the Lenz-Runge vector does not exist.