Stewart, G. W.In 1985 Elsner established a general bound on the distance between an eigenvalue of a matrix and the closest eigenvalue of a perturbation of that matrix. In this note, we show that a similar result holds for the generalized eigenvalue problem. UMIACS-TR-2003-116en-USAn Elsner-Like Perturbation Theorem for Generalized EigenvaluesTechnical Report