The conceptual design of the CasePlan case-based planning and scheduling system is presented. Case-based reasoning is a promising technique for capturing the expertise of contractors who repeatedly build similar facilities and for making such expertise readily available to plan new facilities. To model facilities and organize the planning and construction-related choices made by contractors, a generalized product model is used. This model is specialized for each facility for which a case is stored. A case comprises the facility's design, its construction schedule, and the associated methods and technologies for constructing components and product(s). By matching the product models of cases with those of a new facility, appropriate schedules can be retrieved and adapted to result in a field-executable schedule.