The 1969-72 period has shown an evolution in the belgian european policy. White instituional orthodoxy and federalist teleology had prevailed in the sixties, some pragmatism has been added since Prime minister Gaston Eyskens met President Pompidou in Paris in june 1972. Belgium accepts the launching of a cooperation among the national foreign policies outside the sphere of the EC institutions; regular summits of heads of government are also agreed on. Pragmatism doesn't weaken however the belgian concerns about orthodoxy. Belgian diplomacy is claiming a twofold orthodoxy. The "de lege fata" one insists on the compliance of the institutional practises with the legal provisions of the Treaties and on the extension of the scope of the EC policies by using the faculty provided by art. 235 EC. The constant refusal of the so called "compromis de Luxembourg" and the recurrent plea for the qualified majority voting, or the emphasis put on the powers of the Commission illustrate this kind of orthodoxy. The "de lege ferenda" orthodoxy consists of preventing institutional evolutions from closing the road to the long term federalist aims belgian diplomacy is still working towards for European integration. Hence some dilemmas between pragmatism on short term issues and some dogmatic rigidities which refer to the federalist finality. The discussion about twofold orthodoxy is grounded on a belgian positions' analysis on european affairs which covers the period from the end of the sixties to the belgian positions at the 1996 IGC. By the future perspective of a broader EU enlargement, Belgium will also face a new challenge: will its relative political weight be decreasing in the same time theUnion will extend? Which will be the price for accepting less Belgium in a larger Union?