En-route congestion has for long been a great issue in Europe as well as in the United States of America. Each community has thus developed own solution to face the problem but with different approaches. While in Europe the effort was essentially put into how to anticipate potential congestion issues and prepare the best operational plans to address the risk before traffic is launched airborne, the US invested on how to efficiently react in real-time to forming issues even while traffic is airborne. Looking at how a US-like philosophy could be applicable in Europe is the central subject of this paper. It exposes the specific sources of difficulty, benefits and series of solutions, which could be envisaged in the short-term to adapt the philosophy to the current complex Air Traffic Management (ATM) organization in Europe.