This is a nationwide six-year data study of law enforcement training and professional development in relationship to workplace productivity. Why do we care about law enforcement training and professional development? Because the law enforcement environment is not standing still. Unlawful activity, and in particular drug trafficking strategies, change by the minute. System-wide law enforcement technologies, legislation, regulations and interdiction strategies are constantly adapting. Somehow what we learn from these adaptations has to permeate the law enforcement system. Failing to adapt to changing threats endangers the safety/security of our nation, communities, and officers. It also creates potential liability for law enforcement entities and municipalities (McDevitt et al., 2003; Ross, 1998; Sharpe, 1992). This liability is offset with "effective" professional development and training (U.S. Supreme Court, 1989; Ross, 1998). What then is effective professional development and training? To help answer this question, this study is focused on the evaluation of training provided to High Intensity Drug Trafficking Area (HIDTA) Program law enforcement task forces. Without proper evaluation it is difficult to determine if the professional development is arming officers with the knowledge they need to succeed. What was a successful training program yesterday may not be a cost-effective program tomorrow. This research brings to light the relationship between HIDTA sponsored professional development and effectiveness. It also shows to what extent students agree the training improves job related knowledge, skills, and abilities and to what extent students transfer their new knowledge to the job. This study analyzed six years (2005-2010) of HIDTA enforcement operational and training records to discover a strong (73%) performance predictive for forecasting future and/or past seizure rates based on the number of students trained per year and the number of hours provided. This study also analyzed 56,441 individual student records involving 683,456 training hours isolated from 2010 to find a positive confirmation of students (m = 89.54) that the HIDTA sponsored training improved their job related knowledge and skills; and a positive finding (m = 79.97) that the professional development is being transferred to on the job productivity. What makes the context of this study unique is the autonomy with which individual HIDTAs operate. HIDTAs funded and operated 32 independent training programs in 2010. However, because the programs operate independently, participation ranged from 4 students being trained in one, to 5,510 students in another, with 56 training hours being sponsored in the first, and 73,866 training hours in the second. This study examines these and other findings, then concludes with a bottom-line discussion of what it all means, including: the strong correlation between professional development and work-related outcomes; the high satisfaction and transference of training into practice; individual HIDTA autonomy and independence; the potential influence of other non-training variables upon work success/ failure; and the need for further study. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]