Advance ruling clarifies tax treatment of proposed or ongoing supplies of goods or services, guiding applicants on compliance. The Advance Ruling chapter defines an advance ruling as a decision furnished to an applicant on specified questions relating to the supply of goods or services proposed or undertaken by the applicant. It identifies the Authority for Advance Ruling as the issuing body, the Appellate Authority for Advance Ruling as the reviewing body, and treats an 'applicant' as any person registered or seeking registration, with 'application' referring to the request filed under the advance ruling procedure.