The National Institute for Occupational Safety and Health (NIOSH) has recently been involved in investigations initiated after an astute physician identified a cluster of work-related interstitial lung disease (ILD) among workers at a small plant in Rhode Island that produces nylon flock and nylon-flocked upholstery fabric. A cluster of ILD had been independently reported from a similar plant in Canada, and additional sporadic cases have occurred at other nylon flock plants. This paper reviews results of the NIOSH epidemiological investigation at the Rhode Island plant, summarizes findings from a workshop convened to review lung biopsies and other clinical features of all cases known to have been diagnosed by January 1998, and reports on NIOSH plans for studies at other flock plants.