In this note, we study the following problem, ''Under what condition(s) is it possible to find a single controller which stabilizes k single-input single-output linear time-invariant systems p(i)(s) (i = 1, ..., k)?''. We introduce the concept of avoidance in the complex plane and use it to derive a sufficient condition for k systems to be simultaneously stabilizable. A method for constructing a simultaneous stabilizing controller is also provided and illustrated by an example.
Blondel, V., Campion, G., & Gevers, M. (1993). A Sufficient Condition for Simultaneous Stabilization. IEEE Transactions on Automatic Control, 38(8), 1264-1266. https://doi.org/10.1109/9.233164 (Original work published 1993)