Rationale: Many employers offer workplace health promotion (WHP) programs, such as smoking cessation programs and exercise facilities. There at least two possible economic rationales for employers offering these programs. First, they may offer them in an attempt to improve the health and productivity of their workforce. Second, they may offer them as non-wage compensation to compete for workers. While these two rationales are not mutually exclusive, if the "employment benefit" rationale dominates the "health improvement" rationale, workplace health promotion programs may simply provide an outlet for healthier behavior to workers who would have participated in these activities anyway. For example, and employer who provides exercise facilities may attract workers who are likely to exercise, and offering the facility will not change the probability a worker exercises. Objective: The objective of this paper is to estimate the effect of workplace health promotion programs on health related behavior, controlling for the potential endogeneity of the availability of the program. Methodology: The 1998 National Health Interview Survey Prevention Module has extensive information on the availability of WHP programs and health related behavior for workers. It is possible to determine if a worker has access to a given WHP program and whether or not they participate in the given health related activity (either at work or outside of the workplace). I estimate bivariate probit models with two outcomes: whether or not the worker has access to a given type of WHP program, and whether or not they participate in the health related behavior. The WHP outcome is an endogenous variable in the health behavior equation. The model is identified by the number of employees at the workplace, which is assumed to affect the likelihood of the program being offered, but does not have an independent effect on health related behavior. I estimate the model for the following types of programs and health related behaviors: smoking cessation, exercise, screening for hypertension, hyperlipidemia and cancer, and nutrition/weight control. Results: When ignoring the endogeneity of program availability, all of the programs except for smoking cessation are shown to be positively associated with increases in the given health-related behavior. However, when the endogeneity of program availability is controlled for, the only programs that show a significant and positive influence on health-related behaviors are the three types of screening programs. Exercise and nutrition/weight control WHP programs do not increase the rate of the targeted health-related behavior. Conclusions: The continuing growth in health care expenditures has lead many employers to offer WHP programs. The results of this study suggest that these programs do not independently increase healthy behavior. Smoking cessation programs, exercise facilities and programs and nutrition/weight loss programs do not increase the likelihood that workers will participate in these health promoting activities - at least as these programs are currently constituted. The results could indicate a need for greater information and outreach to encourage employees to access the programs they are offered. Disclosure: This project was funded by the Centers for Disease Control and Prevention, grant number R01 DP000109-01