Site problems Program Execution During Program Execution, a number of management tasks are performed - including planning, organizing, staffing, directing, monitoring, and controlling. The tasks usually must be carried out interactively and iteratively, as the system to be acquired is better defined, especially given the complexities of Department of Defense (DoD) acquisition programs. Many SMC System Program Office (SPO) technical activities are assigned to support Contractors and/or the prime system Contractor through one or more contracts. The allocation of technical responsibilities between the SPO, the prime Contractor, and the support Contractors varies from program to program. Nonetheless, the SPO retains overall program responsibilities. One management philosophy that the Air Force has used to address the complexities of overall program responsibilities is Integrated Product and Process Development (IPPD). In that approach, the product- oriented Work Breakdown Structure (WBS) becomes the outline for planning, organizing, and directing. The Integrated Master Plan (IMP), Integrated Master Schedule (IMS), and Earned Value Management System (EVMS) form much of the program execution planning. The Contractors' organization typically mirrors the upper levels of the WBS. The IMP, IMS, and EVMS supplemented by Technical Performance Measures (TPMs) and other specific risk monitoring devices, are the basis for monitoring. Controlling is accomplished via immediate action plans and longer-term updates to the IMP, IMS, EVMS, and TPMs.