The worksite can be an effective arena to elicit health behavior change. Worksite health promotion programs now exist in 90% of all companies with more than 50 employees. These programs have become prevalent due to the high rates of obesity and lifestyle related diseases that are present in the United States. The purpose of this study was to examine if the social and physical environment is associated with participation in university worksite health promotion programs, self initiated physical activity and healthy nutrition choices. Despite the prevalence of programs, participation rates are traditionally low. Social ecological theory postulates that the environmental factors of an institution can help facilitate positive health behavior. Three California State University (CSU) Campuses without health promotion programs and four CSU campuses with a program participated in this study. Physical activity and nutrition choices were compared for those with and without a program. The campuses with a program were classified as high, medium or low social and physical support as indicated on the Environmental Assessment Tool (EAT). Program participation, physical activity and nutrition choices were compared between campuses designated as high, medium and low support. The results indicated that there was no significant difference in the amount of vigorous and moderate physical activity between those with and without a program, but there were significant differences for walking, with the employees with a program having the highest rates. Program participation was highly influenced by support level, with the high support campus reporting the highest participation rates, followed by the medium and low support campuses. Nutrition choices were not affected presence of a program or level of support. The top barriers to participation were time constraints and marketing. Overall findings indicated that support was highly related to program participation, but employees were still not meeting minimum requirements for physical activity. Therefore, heath promotion directors on university campuses should strive to increase physical and social support and implement best practices to increase physical activity among employees to improve health outcomes, reduce absenteeism and increase productivity. [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.]