International audience During the last decade, consumers have largely benefited from technological advances in the telecom sector: broadband has increased, access to the network became mobile/ubiquitous, the prices of services and terminals have become much more affordable, the usage of technology is more users friendly. Today, the usages continue to evolve and the demand for bandwidth is becoming more and more important. Tomorrow, billions of objects will be connected: people (Phone, digital health, Body Area Networks), cars (Smart Cars, Intelligent Transport Systems), smart cities, etc. These connections will not be wired: most of them will be wireless. This raises the issue of vercrowding and congestion of the wireless networks. Far beyond the technology development and under the pressure of increasing usage, the question arose as to the effective and efficient use of spectrum and through it, the issue of competition and innovation in sectors using spectrum (including mobile). Numerous studies have shown the existence of white space, "holes" in spectrum use, and thus as a corollary the existence of potential social and economic inefficiencies. Technically, technologies for managing dynamic spectrum emerge: this is for example the case of cognitive radios. The theoretical issues underlying dynamic spectrum management are important: Should one share its spectrum with others? Under which conditions? How? What collaborative models should be used? What rule of risk sharing? What incentives for the owner of the infrastructure? Shall we move towards a new vision of spectrum regulation? How to adapt the regulatory framework for electronic communications in Europe? After a demonstration of the inefficiency of the ac tual system in Europe, our paper explores the regulatory reform required in the transition towards a ‘shared access spectrum'. It introduces the new spectrum management system paradigm based on recent emerging concepts, i.e. Collective Use of Spectrum (CUS), Authorized Shared Access (ASA), icensed Shared Access (LSA), which have been developed to allow a more efficient use and management of the spectrum resource. Then, we determine objectives to reach to sustain future connected word and we analyze the different obstacles that prevent the transition. The main objectives are: dynamic and collaborative use, non discriminatory use, incentives to promote efficient use from spectrum holders. To conclude we explore the importance of competition policy in transitioning spectrum management system. This may create a tool for government intervention in the transition to a collaborative spectrum use.