The authors use data from the 1984 Survey of Income and Program Participation (SIPP) to investigate whether employer-provided health insurance reduced worker mobility (a phenomenon termed “job-lock”). The SIPP provides Information on variables—particularly pension receipt, job tenure, and spouse job change—that were omitted from previous studies and are, the authors argue, key to the estimation of well-defined mobility models. For dual-earner married men and women, the authors estimate a model that accounts for the interaction between husbands' and wives' job change decisions. For both married and single individuals, the results provide fairly strong evidence of job-lock among women, but only weak indications of job-lock among men. The authors speculate that this finding reflects higher health care use by women than by men.