The evolution of technology is increasingly blurring the once clear distinction between the aviation and space sector. Technologies that combine elements of the two fields such as satellite-guided unmanned aerial vehicles, sub-orbital flights and space-based Global Flight Tracking are on their way towards full global implementation. All these systems make use of radio spectrum for telemetry, tracking and command (TT&C) and voice/data transmission, relying upon a combination of space and terrestrial communication services subject to the ITU Radio Regulations. The management of the radio spectrum used by these technologies represents a challenge for the ITU Radiocommunication Sector on a double level. At first, it will need to adapt its own regulatory framework by introducing new spectrum use parameters and procedures or by amending the existing ones. As recognized by ITU Resolution 772 with reference to stations on board of sub-orbital vehicles, indeed, the current ones are likely inadequate for international use of relevant frequency assignments. Secondly, the safety-of-life aspects of the above-mentioned technologies as well as their required integration in global Air Traffic Management will require a tighter coordination with ICAO, which is the UN Specialized Agency in charge of the safety of international civil aviation. Its mandate includes also the safety aspects related to radio communication and navigation services, which are regulated in Annex 10 to the Chicago Convention. Such coordination is currently based upon the cross-participation of the technical experts of the two agencies in the respective technical preparatory works. In this sense, it has to be recalled the key role of the ICAO Frequency Spectrum Management Panel (FSMP) and of the ITU-R Study Groups 4 and 5. An increased participation of the interested private and public stakeholders, however, will be crucial to ensure that the final regulatory output reflects the actual needs of the industry and of the public. In view of the increasing workload and complexity of the task, it could be even envisaged the creation of a joint ITU-ICAO working group on the basis of the existing Joint IMO/ITU Experts Group on Maritime Radiocommunication Matters. A mixed and in principle balanced representation of experts from the two agencies, from the different communities of national regulators as well as from the private industry would ensure that all interests and expertise are given proper relevance, while the UNOOSA could participate with observer status in representation of the space community.