This testimony concerns the role of a Task Group organized to investigate the effects of pesticide exposure on field workers in the United States in early 1972. The Task Group also examined the entire range of activities with pesticides from manufacture to application. During 1971 NIOSH developed a priority list for criteria documents to be developed and transmitted to OSHA for their consideration in setting new occupational health standards. Several organophosphorus insecticides appeared near the top of the list and criteria documents for several of these substances appeared between 1972 and 1976. These documents contain recommendations for permissible exposure limits, medical surveillance, labeling and posting, personal protective equipment and protective clothing, informing employees of hazards, work practices, sanitation, and monitoring and record keeping. NIOSH maintained close contact with the EPA during research on pesticides through a formal interagency agreement. NIOSH also cooperated on an international level in the area of pesticides through the World Health Organization. Letters have been sent to approximately 40 producers of pesticides and formulators requesting information on the use of biologic indicators of exposure, engineering controls, specifications for the conditions under which personal protective devices should be required, the need for medical examinations, work practice procedures, the type of records maintained, and the use of warning devices and labels as part of an effort to develop recommendations for all pesticides in general during their manufacture and formulation.