The legacy of Air Traffic Management (ATM) evolution in Europe has resulted in today’s highly fragmented, country-based, services. A consequence of this fragmentation, there is a negative impact on the cost in the provision of ATM service in Europe. A fundamental goal of the Single European Sky initiative is to “provide ATM services to airspace users at a cost of at least 50 % less”. The notion of Common Service aims to contribute to this goal. Common Services, defined as “a service that provides capability to consumers in the same way that they would otherwise need to provide themselves”, aims to mitigate this issue. Common Service approach follows a general principle within the Single European Sky initiative that encourages the harmonisation on the provision of common air navigation services wherever it is possible.The main benefit of this approach is to deliver enhanced cost effectiveness to both the providing and consuming organisations and this could in turn potentially benefit the whole chain in the European air transportation business, making it more attractive as means of transport. Additionally, there could be a positive impact on other ATM performance areas as well, such as capacity, safety, flight efficiency, etc.The providing organisations would benefit from economy of scale, while the consumers would not need to maintain and update proprietary solutions anymore. Overall, a better rationalisation of deployment should be expected.Therefore this Common Service approach, if it is proved to be successful, could be viewed as an essential means to improve the overall cost effectiveness of the ATM business in Europe. PJ15 encompasses air navigation service providers and ground industry covering both provider and consumer perspectives. Thanks to its unique combination of operational and technical knowledge and experience, the group is in an excellent position to deliver high-quality results.