The fourth in a series of leaflets designed for dissemination of information on school building, this publication describes a caseworks subsystem consisting of storage systems, surface systems, plumbing and electrical services, and seating. The technical performance specifications for this subsystem and nine others were developed as a product of the Toronto School Board's Study of Educational Facilities (S.E.F.). The caseworks design consists basically of a series of containers, panels, and bases of various sizes on a 60-inch (1500mm) module. Square and rectangular containers, in nine modular sizes, are the basic building blocks of the subsystem. These can be arranged and attached in limitless configurations, and with the addition of subsystem accessories such as shelves, doors, and dividers, can adapt to specific functions demanded in schools. Because of this modularity, containers are moulded of rigid self-skinning polyurethane foam, as are library card catalogue drawers and container doors. Shelves are steel pans filled with light density urethane for strength and rigidity. (Photographs may reproduce poorly.) (Author/MLF)