Abstract: In a distributed context, mutual exclusion algorithms can be divided into two families according to their underlying algorithmic principles: those which are permission-based and those which are token-based. Within the latter family a lot of algorithms use a rooted tree structure to move the requests and the unique token. This paper presents a very general information structure (and the associated generic algorithm) for token-and treebased mutual exclusion algorithms. This general structure does not only cover, as particular cases, several known algorithms but also allows to design new algorithms well suited to topology requirements.