The T sets, also referred to as the Tangara trains, are a class of electric multiple units that currently operate on the Sydney Trains network. Built by A Goninan & Co, the sets entered service between 1988 and 1995, initially under the State Rail Authority and later on CityRail. The T sets were built as "third-generation" trains for Sydney's rail fleet, coinciding with the final withdrawals of the "Red Rattler" sets from service in the late 1980s and early 1990s. The Tangaras were initially built as two classes; the long-distance G sets and the suburban T sets, before being merged after successive refurbishments.

Sydney Trains is the operator and brand name of the train network serving the Greater Sydney metropolitan area in New South Wales, Australia. The network is a hybrid urban-suburban rail system with a central underground core that covers 369 km (229 mi) of route length over 813 km (505 mi) of track, with 170 stations on eight lines.