A psychologist is a professional trained in the science of how people think, feel, behave and learn.
In Australia, psychology is a regulated profession. This means that people who call themselves a psychologist or say they are practising as a psychologist must be registered with the Psychology Board of Australia (PsyBA) and listed with the Australian Health Practitioner Regulation Agency (AHPRA).
Registered psychologists are required to have a minimum of six years of university training and supervised experience, and to engage in ongoing education to keep their skills and knowledge up to date.
They must also adhere to certain strict standards to keep their registration, and must provide professional services according to a strict code of ethics, written by the APS.
You can check on the AHPRA website to see whether a person is registered as a psychologist.