The success of a commuter rail system depends on cultivating a ridership base on which to expand the system. Cultivating this ridership depends on offering a quality transportation option to commuters. Characteristics of commuter rail systems in the United States present significant challenges. Commuter rail has been implemented only on existing rail right-of-way (ROW) and infrastructure in the United States. Existing rail ROW does not often coincide with current commercial and residential demand centers and necessitates the use of a circulator system to improve the accessibility of the system. The commuter rail circulator network design problem (CRCNDP) addresses a particular aspect of the commuter rail trip, seeking to improve the performance of the entire system through accurately modeling the portion of the trip from rail station to the final destination. This final leg includes the trip on the circulator vehicle and the walking trip from the circulator stop to the final destination. A detailed description of the CRCNDP is provided, as well as a case study that will seek to illuminate the performance of the CRCNDP using three operational strategies.