The Aptis Advanced Technical Supplement provides information for test users that is specific to the Aptis Advanced test within the Aptis Test System. The Aptis Advanced Technical Supplement is intended to be used in conjunction with the main Technical Manual (O’Sullivan, Dunlea, Spiby, Westbrook, & Dunn, 2020), which provides detailed information on the system as a whole. This supplement focuses on details of the test and task specifications specific to the Aptis Advanced test, with specifications for each of the five components (Grammar and Vocabulary, Listening, Reading, Speaking, Writing) and detailed information on task specifications and rating.