Moonlighting workers represent a significant and growing percentage of the labor force, yet few studies examine the reasons for and economic consequences of this decision. Possible motives for moonlighting include the inability to work sufficient hours on the primary job and the desire for a nonpecuniary aspect of the second job that is unavailable on the primary job. Using data from the SIPP, we present descriptive and econometric evidence on moonlighting behavior in an attempt to reveal who moonlights and why. Our results suggest that both motives are present, with constraints on the primary job being the more common one. In addition, we find that the typical moonlighter remains somewhat poorer than the average worker despite working full time on his primary job and part time on a lower‐paying second job.
