A detailed study of a transit corridor. An alternatives analysis focuses on alternative transit solutions to the transportation problems identified during the Pre-AA. An AA will include a range of alternatives including one or more rail options, a bus guideway alternative, and a non-guideway (TSM) alternative representing the best solution possible without an investment in new infrastructure.

a study of high-type highway or transit improvements of substantial cost expected to have a significant effect on capacity, traffic, level of service, or mode share at the transportation corridor level. This satisfies the same requirements as what was previously referred to as Major Investment Study (MIS).

A process required by the Federal Transit Administration (FTA) to prioritize and decide on the most appropriate transit projects within a region.