What are the prospects for trilateral concord among Britain, France and Germany in terms of defence policies? Would more institutionalised links among them lead to more convergence of their defence policies? To answer these interrogations, this article investigates the relation between policy convergence and institutionalised cooperation, in particular by studying whether and when one is a prerequisite to the other. First, this article examines the extent to which these countries' defence policies have converged since the end of the cold war based on several indicators: their attitudes towards international forums, their defence budgets, the structure of their armed forces and their willingness to use force. Second, we study each of the bilateral relations between the three states to qualitatively analyse their degree of institutionalisation and the convergence of their defence policies. This article concludes that contrary to the arguments of many discussions, think-tank reports and political actors, there is no evidence that institutionalised cooperation leads to policy convergence as far as defence is concerned.