The growing number of incidents of soil and groundwater contamination with nonaqueous phase liquids (NAPLs) has caught the nation unprepared. A number of challenges confronted the three agencies involved (government, academic research community, and private industry). The urgency of clean-up necessitated that they progress swiftly in several directions: assessment and characterization of NAPL-contaminated sites, assessment and management of the risks involved, development of remediation technologies which are both technically and economically feasible, and development of concepts involved in fate and transport of the NAPLs in their various forms in the subsurface. While the past decade has seen considerable progress in all these areas, a synthesis of the developments made in various disciplines and the progress achieved in the three sectors is essential to progress further in this important area. This was the intended purpose of the NAPLs conference. Specific topic areas covered in this proceedings are: site assessment and characterization; remediation technologies; and analysis and modeling of fate and transport. In addition, case studies of some NAPL sites are recounted.