Outsourcing of support services (non-core activities) has now become an established trend for many UK organisations, both in the private and public sectors. The public healthcare sector is not excluded from this. Outsourcing, once used as a means to reduce costs, has now acquired strategic significance in organisations. Very little research has been carried out on the decision-making process of outsourcing in the public sector, particularly in healthcare. For many years, organisations have outsourced their support services to best-in-class service providers. This paper reviews the available literature on critical decision making in outsourcing support services, with particular emphasis on the selection process. It can be concluded that not only support services (non-core activities) are candidates for outsourcing; there are proposals to outsource core activities under certain circumstances. Understanding among staff about which activities in the organisation are core and non-core is also important. Therefore, it is crucial for organisations to make correct decisions when deciding which activities to outsource, as they have a substantial effect upon the future of the organisations.