TRB's Transit Cooperative Research Program (TCRP) Synthesis 120: Use of Automotive Service Excellence Tests Within Transit documents how the Automotive Service Excellence (ASE) program is accepted and used within the transit bus maintenance community. The ASE program is nationally recognized as the standard industry credential provider for automotive professionals. The report explores how a cross section of transit bus maintenance personnel view the ASE certification program and summarizes their perspectives to improve ASE certification acceptance and participation.