Managing the engineering interfaces of mass rapid transit (MRT) projects is difficult and exhausting work because thousands of complex interrelated construction interfaces are embedded among multiple subworks and subsystems. When these interfaces are not revealed and thoroughly preplanned to achieve timely execution, they generate countless disputes among project parties and delay the overall progress considerably. This paper discusses a stepwise procedure to provide an empirical and comprehensive solution for managing the engineering interface of MRT projects. The proposed procedure involves four steps: (1) identification of the key interface correlation and work scope using a work-breakdown structure; (2) allocation of interface scope responsibilities and criteria using a phase approach; (3) preplanning the interface work items; and (4) setting up interface organizations using veto authorization. The proposed method is suitable for design-build or design-bid-build MRT contracts, thereby benefiting practitioners of interface management in the relevant field. (C) 2017 American Society of Civil Engineers.