To control the migration of radioactive and hazardous wastes currently contained underground, barriers made of natural materials and man-made substances are constructed atop, and possibly around, the contaminated area. Barrier Technologies for Environmental Management provides a brief summary of the key issues that arose during the Workshop on Barriers for Long-Term Isolation. Recurring themes from the session include the importance of quality control during installation, followed by periodic inspection, maintenance, and monitoring, and documentation of installation and performance data. The book includes papers by the workshop presenters.