This dissertation is a case study of a professional development effort in a large urban school district over the course of one school year. With their district identified for improvement under the requirements of the Elementary and Secondary Education Act of 2001, district leaders were under pressure take corrective action. As part of their plan for change, district staff provided their school leaders with this yearlong professional development in data use, expecting school leaders to learn to analyze and use data in their instructional and administrative decision making. The planners designed the program to roll out in stages each month, using a train-the-trainers model, with the expectation that every participant, no matter what their prior experience or expertise with data use, would receive exactly the same information, presented in precisely the same way. District office staff presented the training to middle level administrators, who then became the trainers and passed the information to principals and other school leaders. District leaders held the theory of action that if they made data easily available to school leaders, there would be a chain reaction leading ultimately to improved student learning. My investigation was to see if the reasons district leaders gave as governing their actions manifested in what they did: if their theory of action was in sync with their theory in use. Together with three other researchers, I observed monthly meetings to train the trainers and also monthly professional development sessions for school leaders. We interviewed district and school leaders about their intentions and about the way school leaders absorbed the data use information. I analyzed the slide presentations designed by the planners and observed how the trainers presented them to school leaders. I considered whether train-the-trainer could be illustrated with the metaphors of a bucket brigade or a cascade. I found that the train-the-trainers model resulted in transmission of a garbled message, as each trainer processed the message through her or his own experience and passed it along in somewhat altered form. I concluded that bucket brigades are messy, and professional development planners should expect their messages to evolve. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]