Headway management can potentially reduce passenger waiting time and on-board crowding on high-frequency services. In this study, a headway control experiment was conducted and evaluated for Washington Metropolitan Area Transit Agency routes 70 and 79 in Washington, D.C. The field experiment is evaluated by performing a before–after empirical evaluation. The organizational process and challenges involved with the implementation are discussed. Overall, a reduction of 26% in passenger excess waiting time was attained, which implies annual time savings that translate into US$1 million. Even though the field experiment implementation was far from ideal, the benefits obtained so far might pave the road to a long-term commitment to shift into a fully controlled headway-based management.