GST practitioner authorisation permits authorised representatives to file returns and represent registered persons, subject to enrollment and conduct rules. Authorisation establishes the role, enrollment, powers and controls for a GST practitioner. Eligibility requires citizenship, sound mind, non insolvency, no serious conviction and specified professional or academic qualifications or prior enrollment. Enrollment is by prescribed application and certificate; continued enrollment may require passing notified examinations. Authorized activities include furnishing supply details, filing returns, making electronic deposits, filing refund claims, applying for registration amendment/cancellation, and representing the principal before tax authorities. Accuracy remains the registered person's responsibility; electronic confirmation is required and misconduct can lead to show cause and cancellation.