The European Union has remained stable despite all its past and current challenges. This essay explores the reasons for that. We argue that the secret behind its stability lies in its system of negotiation. Against this backdrop, we analyse two recent challenges of the European Union. First, we show how domestically bound European governments were able to bring about a stable internationally negotiated solution for what became known as euro crisis. By means of game theory we boil down why the European Union remained stable even after havoc struck. Second, we analyze the dynamics behind the failed negotiations with Ukraine that have led to the current conflict. Thereby, the role of vested interest in negotiations for stability is emphasized. We prognosticate that due to the very same vested interests that led to the failure of the negotiations, Ukraine will remain united and return to stability in the mid-term. Finally, we conclude that, despite challenges like these, the European Union never experienced a crisis in terms of system theory since it never fell short to fulfil its purpose which is to allow for peaceful cooperative solutions.