Assessing the achievements of the European Union Community over the last 50 years, the article analyzes three great economic projects that shaped the vision of Europe as a unified economic area which is a key link of world economy. The discussed projects include: the program of a unified internal market, the Economic and Currency Union, and the Lisbon Strategy. The projects are assessed from the point of view of a philosophy of integration proposed by Jean Monnet, and based on the principle of a gradual transition to subsequent stages of cooperation in effect of practical achievements and related concepts of functionalism and neo-functionalism. The Monnet method assumes Europe's gradual federalization by 'attaining federal solutions due to creation of real bonds between states and by developing corresponding political systems'. In turn, functionalism theories describe the dynamism of European integration in terms of the concept of 'spill-over logic', i.e. within the framework of expanding the tasks of integration onto subsequent spheres and areas, following the acquisition of the ethos of cooperation and reaching a procedural consensus for the realization of diversified interests. Fifty years of European Union's history have proven those concepts correct and represent a slow and gradual development of integration processes towards a tighter cooperation based on attaining subsequent stages from a unified market to currency union, and further on to a strategy of making the Union the world's most competitive economy. However, the process is not a linear one, it encounters barriers and limitations, and for this reason requires commitment both on the part of EU's institutions as well as the governments of member states so that the great project of a common Europe might not be dissipated.