Abstract: Very costly professional-level judgments needed to comply with scientific and statutory restrictions on hazardous-waste segregation, shipment and disposal are collected cumulatively in a database for a very large number of hazardous waste materials. Many of these materials are statutorily designated or scientifically recognized, or both, as posing a significant physical danger to humans, other organisms, or the ecosphere generally. Later many consignments of particular materials are received (or identified before receipt, in a batch mode of operation) and classified very inexpensively--using nonprofessional-level personnel--by reference to the computerized database. Reversion to professional-level judgments occurs only if a material not previously encountered is received. Each consignment of each material is classified and handled consistently with all other consignments of like material, and in accordance with the professional-level judgments embodied in the database.