The present invention is directed to a modular mold system comprising at least two mold designs or mold sizes. In a further embodiment, the present invention is directed to a modular mold system comprising molds that are the same design but vary in size and cavitation. In a further embodiment, the present invention is directed toward a modular mold system for production of a family of a part designs. In a further embodiment, the present invention is directed toward a modular mold system developed from a part design and a part size. Another embodiment of the present invention would be directed toward a modular mold system comprising at least two mold sizes comprising standardized and identical components.