This document specifies a method for sampling, handling and extracting enchytraeids from terrestrial field soils as a prerequisite for using these animals as bioindicators (e.g. to assess the quality of a soil as a habitat for organisms).Basic information on the ecology of enchytraeids and their use as bioindicators in the terrestrial environment is included in the Bibliography.This document applies to all terrestrial biotopes in which enchytraeids occur. The sampling design of field studies in general is given in ISOÂ18400-101. These details can vary according to the climatic/regional conditions of the site to be sampled and an overview on the determination of effects of pollutants on enchytraeids in field situations is given in ReferenceÂ[6].Methods for some other soil organism groups such as earthworms or arthropods are given in ISOÂ23611-1, ISOÂ23611-2, ISOÂ23611-4 and ISOÂ23611-5.This document is not applicable for very wet or flooded soils and might be difficult to use under extreme climatic or geographical conditions (e.g. in high mountains).When sampling soil invertebrates, it is highly recommendable to characterize the site (e.g. concerning soil properties, climate and land use). However, such a characterization is not covered by this document. ISOÂ10390, ISOÂ10694, ISOÂ11272, ISOÂ11274, ISOÂ11277, ISOÂ11461 and ISOÂ11465 are more suitable for measuring pH, particle size distribution, C/N ratio, organic carbon content and water-holding capacity.