The United Kingdom’s exit from the European Union has resuscitated academic discussions on the topic of the certainty of the unfolding of disintegrative trends in the united Europe. Nevertheless, no general perception has emerged yet of how Brexit is likely to influence the organizational prospects and viability of European integration. In most cases, the conceptualizations do not escape the dichotomy between integration and disintegration as two extreme states in international relations. In fact, these are two processes that are complexly co-related. Each of them can include a wide array of structural arrangements, a certain differentiation dynamism, different levels of centralization in separate domains, as well as certain (variable) numbers of participants in distinct arrangements. In this article, we consider the meaning of Brexit as a condition of further European (dis)integration, based on Alexander Bogdanov’s theory of organization. This theory allows us to reconsider the established renderings of such key notions as integration, disintegration and differentiation.New insight is gained into the after-effects of prior Europeanization for the political system of the United Kingdom. The cases of the Economic and Monetary Union and the Northern Ireland Protocol receive separate treatment. The latter case presents a path-breaking design for differentiated integration with subnational region participation. Yet, to realize the potential of the Protocol in full, political will is needed from both London and Brussels.On the most basic level, once this large country left the European Union, one could hardly imagine any of its remaining 27 members being able to block the further progressive development of European integration. At the same time, it has to be acknowledged that, in order to make headway in terms of integration, the EU system, rather than unification and centralization, is in need of intensive differentiation. Meanwhile, the supranational institutions, above all the European Commission, remain oriented towards uniform integration as a priority. This could lead to the EU integration policy becoming less effective.