In this paper we review a number of coalitional solution concepts for the analysis of cartel and merger stability in oligopoly. We show that, although so far the industrial organization and the cooperative game theoretic literature have proceeded somehow independently on this topic, the two approaches are highly inter‐connected. We show that different assumptions on the behaviour and on the timing of the coalitions of firms yield very different results on the associations of firms which are stable. We conclude by reviewing some recent extensions of the coalitional analysis to oligopolistic markets with heterogeneous firms and incomplete information.