This work set out to determine the cause or causes of the significant growth in the time required to develop and field new technology in major weapon system programs in the U.S. Department of Defense that has occurred over the last sixty years. The effort revolved around the analysis of twenty-one case studies of major technology development and acquisition programs (seven each from the early, late, and post Cold War periods, respectively). Primary causal factors are identified and discussed as well as recommendations to remedy or mitigate them. / text