In this paper, we address the problem of deriving sensible information from a collection of argumentation systems coming from different agents. A general framework for merging argumentation systems from Dung’s theory of argumentation is presented. Each argumentation system gives both a set of arguments and the way they interact (i.e. attack or non-attack) according to the corresponding agent. The aim is to define the argument system (or the set of argument systems) that best represents the group. Our framework is general enough to handle the case when agents do not share the same set of arguments. Merging argumentation systems is shown as a valuable approach for defining (sets of) arguments acceptable by the group.