This paper uses establishment data to estimate the determinants of using agency workers. It contends that there is a class of family-friendly practices including workplace nurseries, flexitime, home working, and job sharing that promote the norm of the “ideal worker” who concentrates on work. Because such practices increase the ability of employers to direct worker effort, they will be associated with a lower use of agency workers. Our findings confirm this hypothesis. The implication is that any growth in family-friendly practices may work against the ongoing expansion in agency jobs.