Volume: 17 • Number: 5 • Pages: 339-341

A paper published in this journal in 1984 ("Some results on simultaneous stabilization", Vol. 5, pp. 205-208) presents a necessary and sufficient condition under which plants with identical unstable poles and zeros, but differing by their stable poles and zeros, can be simultaneously stabilized (Theorem 3, p.207). We show by a counterexample that the condition presented in that paper is sufficient but not necessary.