6 Operations management may be defined as the design, operation, and improvement of the production systems that create the firm's primary products or services. OM is a field of management, while OR/MS is the application of quantitative methods to decision making in all fields, and IE is an engineering discipline. Five P's of operations management: people, plants, parts, processes, and planning and control systems. People are the direct and indirect workforce. Plants include the factories or service branches where production is carried out. Parts include the materials (or, in the case of services, the supplies) that go through the system. Processes include the equipment and steps by which production is accomplished. Planning and control systems are the procedures and information management uses to operate the system.