This paper investigates the importance of labor turnover in the evaluation of health care options. Using data from the Survey of Income and Program Participation (SIPP), it describes labor turnover for persons with and without employer-paid health insurance. It then evaluates the effect of workers' employment patterns on their "effective health insurance coverage." The authors use a health expenditures simulation model to estimate expenditures under alternative specifications of insurance and for different covered populations. Simulations are performed for cases where the deductibles and out-of-pocket spending limits are reinitialized with each new insurance plan resulting from a job change. These are contrasted with cases in which insurance parameters such as deductibles and out-of-pocket caps are coordinated over job changes. In four sections, this article: (1) provides an overview of the current provision of health insurance in the U.S. and proposals to solve the problem of the uninsured; (2) describes the SIPP data used, and documents current levels of job mobility and how this differs for job holders who do and do not receive employer-paid health insurance through their jobs; (3) describes the health expenditures simulation model and reports the results of simulations that investigate the inter-relation between insurance coverage and patterns of labor turnover; and (4) presents conclusions and directions for future research.