The Air Force has several options for sustaining weapon systems and components but has, in recent years, increasingly chosen contractor logistics support (CLS) over organic support. Still, questions remain about costs and efficiency, even about whether CLS is the best option. The authors explored these by reviewing the relevant laws and regulations, analyzing program and contract costs, and speaking with individuals involved in managing and contracting and budgeting for CLS contracts. The authors noted that CLS contracts have often been awarded to original equipment manufacturers because, lacking the technical data, the Air Force could not choose a third party. Without competition, the price of CLS contracts is often determined by analysis and negotiation. They also noted that contracts that guarantee large annual sums limit the Air Force's ability to adjust when its own funding changes. The Air Force has taken steps to assess requirements for technical data early in the acquisition process and to use contracting provisions that allow funding levels to be more flexible. Requiring the reporting and collection of detailed CLS costs in a standardized format and making the data available to program offices across the Air Force would further strengthen the Air Force's ability to obtain favorable prices. Book jacket.