5G will revolutionize the way ICT and Telecommunications infrastructures work. Indeed, businesses can greatly benefit from innovation introduced by 5G and exploit the new deep integration between ICT and networking capabilities to generate new value-added services. Although a plethora of solutions for virtual resources and infrastructures management and orchestration already exists (e.g., OpenDaylight, ONOS, OpenStack, Apache Mesos, Open Source MANO, Docker Swarm, LXD/LXC, etc.), they are still not properly integrated to match the 5G requirements. In this paper, we present the 5G Operating Platform (5G-OP) which has been conceived to fill in this gap and integrate management, control and orchestration of computing, storage and networking resources down to the end-user devices and terminals (e.g., smart phone, machines, robots, drones, autonomous vehicles, etc). The 5G-OP is an overarching framework capable to provide agnostic interfaces and a universal set of abstractions in order to implement seamless 5G infrastructure control and orchestration. The functional structure of the 5G-OP, including the horizontal and vertical interworking of functions in it, has been designed to allow Network Operators and Service Providers to exploit diverse roles and business strategies. Moreover, the functional decoupling of the 5G-OP from the underneath management, control and orchestration solutions allows pursuing faster innovation cycles, being ready for the emergence of new service models.