Equivalence of multistage interconnection networks is an important concept because it reduces the number of networks to be studied. Equivalence among the banyan networks has been well studied. Occasionally, the study was extended to networks obtained by concatenating two banyan networks (identifying the output stage of the preceding network with the input stage of the succeeding one). Recently, equivalence among the class of networks that are obtained from banyan networks by adding extra stages has also been studied. Note that all these above-mentioned networks are in the general class of buddy networks. In this article we study equivalence of buddy networks with an arbitrary number of stages. © 2005 Wiley Periodicals, Inc. NETWORKS, Vol. 46(4), 171–176 2005