To provide some guidance in the early planning and conceptual design of downtown people movers, a rough, aggregate approach was developed for determining the effects on ridership of major downtown people movers design and policy decisions. The approach is an abstract, parametric analysis that uses aggregate relations and simplified assumptions to show how ridership of downtown people movers is influenced by (a) alternative downtown people movers design configurations (ie, such factors as number of stations and station spacing),(b) operating characteristics and policies (ie, such factors as speeds, headway, and fare), and (c) the size, density, and distribution of activities in the central business district. Trips in five categories are examined separately for possible diversion to downtown people movers: regional trips to the central business district by automobile and transit and internal central business district trips by automobile and transit and internal central business district trips by automobile, transit, and walking. The many combinations of site, system, and service variables tested allow general implications to be drawn from the numerical results. Among the most important are the following:(a) station spacings below or above the 366-488-m (1200-1600-ft) range begin to be less efficient;(b) systems that interface with regional transit at a central business district fringe station divert more transit passengers than does a central delivery arrangement, except in large, spread central business districts;(c) parking fees and capacities at downtown people movers stations are major factors in potential diversion of automobile users to downtown people movers; and (d) downtown people movers service policies have less effect on ridership than fares, except where downtown people movers are in competition with the local central business district bus./Author/