GPs refer patients to multiple specialists based on the particular medical issue at hand. A Specialist is someone who has the skills to manage that particular problem. Generally there are multiple specialists available to handle a particular medical issue. Most GPs have a good working relationship with particular specialists and so therefore refer patients on that basis. You can ask your GP to refer you to a specialist of your choice. Some specialists only manage patients in the private hospital system, as they don’t hold a public hospital appointment. Dr Ahmed can manage patients both in the private and public hospital systems.