This paper describes a procedure for considering mechanical requirements, manufacturing costs, and material selection in the design of injection molded parts. The benefit of this approach is the simultaneous consideration of the implications of material selection and part geometry on estimated manufacturing cost during candidate design selection. The current implementation uses the allowable deflection of a flat plate as an example performance measure. Manufacturability concerns include required part thickness and gating scheme to adequately mold the part, and a resulting cycle time based on part cooling time estimates. Part manufacturing cost includes material cost, cycle time, and production costs. A PC-based and CAD-integrated program illustrate our proposed procedure.