Practical Commissioning's Jargon Buster sources a definition for specialised commissioning
Although services in the NHS are commissioned by PCTs, there are particular arrangements for commissioning specialised services. Specialised commissioning seeks to ensure that the needs of those with rare diseases, or who require specialised services not available in all local hospitals, are met effectively. Examples of such services include heart, lung and liver transplants, children's heart surgery and neurosurgery, specialised burn care and the treatment of illnesses such as severe immune deficiency or rare neuromuscular disease. These services are often expensive and unpredictable so PCTs have come together to commission such services collectively and thereby share the financial risk.
These services are often best provided in a small number of regional specialist centres so doctors and nurses can develop their skills by seeing as many such patients as possible.