General purpose many-core architectures of the future need new scalable operating system designs and abstractions in order to be managed efficiently. As both memory and processing resources will be ubiquitous, concurrency will be the norm. We present a strategy for operating systems for such architectures, presenting the approach we take for our SVP (Self-adaptive Virtual Processor) based Microgrid many-core architecture. Aspects such as scheduling, resource management, memory protection and system services are covered, with a detailed discussion on the design of an I/O subsystem for the Microgrid.