It has been shown that the use of Health Information Technology (HIT) is associated with reduced cost and increased quality of care. This dissertation examined the use of registries in Patient Centered Medical Home (PCMH) practices. A survey questionnaire was sent to a nationwide group of clinics certified for being a PCMH. They were asked to provide information about their payer mix, implementation barriers, registry implementation, registry use, and clinic satisfaction. The survey instrument was validated by an expert panel which included practitioners and researchers. Statistical methods including Structural Equation Modeling were used for analysis and to test the research hypotheses. The majority of medical home practices that responded used some type of computerized registry, either with basic patient information or integrated with detailed clinical information. And on average, they somewhat used registries for population management, individual health management, proactive care and planned care visits. All practices encountered some combination of barriers when implementing a medical home program. Most practices reported clinic satisfaction at least improved after becoming a medical home. The results of the analysis show that indeed payer mix, in particular Medicare and private insurance, has a significant relationship with level of registry implementation. There were no significant relationships between barriers and registry implementation or use. More sophisticated registry implementation led to greater registry use. And registry use is associated with increased clinic satisfaction. This research fills an important gap in understanding Health IT use, registries in particular, among Patient-Centered Medical Homes. The findings suggest that: 1) Implementation barriers may not be influencing use of computerized registries in medical home practices; 2) Using more sophisticated computerized registries facilitates registry use, which can help improve clinic satisfaction; 3) Payer mix may influence use of more sophisticated Health IT in medical home 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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]