Each agency referenced in this category has a "general listing" that discusses purpose and structure, provides a locator/operator contact, and when possible, director's office and public affairs type contacts.
Additional "divisional listings" are provided for some agencies to identify in more detail the different groups in the agency (divisions, bureaus, sections, departments, etc.) that provide assistance or regulation; e.g. there are many listings to describe the EPA.
Related References
Federal/national agencies are also commonly referenced in the EnviroSource categories Hotlines/Clearinghouses, Federal/National - Libraries, and Research Centers.