The importance and use of data and information to make sound programmatic decisions are receiving increased attention as state and federal funding for public health programs grows tighter and as demands for accountability continue. This dissertation provides insight into fundamental questions regarding the utilization of a Web-based reporting system on knowledge management practices for Tobacco Prevention Programs and examines what happened in Texas after the merger of the Tobacco Prevention Program into the Substance Abuse Prevention Program. A phenomenological qualitative approach was used to explore meaning of actions and to identify common themes as they relate to information sharing and utilization of Texas' Program Management and Tracking System (PMATS). Twenty-four semi-structured interviews were conducted. First, core functions of PMATS are examined through the experiences of its end-users; and second, the impact of the merger on retention and use of PMATS within the Department of State Health Services is explored. Four themes were identified as they relate to core functions of PMATS, including its use as a codification system, its use to track performance measures, and its use for report generation and for programmatic decision-making. These four primary uses of PMATS remained the same pre- and post-merger, although how the systems were utilized during these periods differed. A central theme that permeated all interviews was the impact of the merger of the Tobacco Control Program into the Substance Abuse Program on individual beliefs and attitudes (i.e., job security, low morale, etc.), on systems characteristics (i.e. feedback, internal reporting structures, etc.), and on organizational culture (i.e., training, leadership, etc.). Since entering into PMATS was contractually required, individual attitudes and beliefs did not impact its use. However, competing IT systems, lack of a champion, lack of knowledge and support by upper management, and lack of communication were identified as key influences on systems characteristics and on organizational culture, which ultimately contributed to the termination of PMATS. Both applied research and practice recommendations are discussed, including IT due diligence, creating a knowledge culture, and network analysis of information sharing practices. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]