For those not familiar with the Department of Justice and the components of it such as the FBI, DEA etc. here is a chart and overview

Home » Justice Management Division

ORGANIZATION, MISSION AND FUNCTIONS MANUAL

Department of Justice Overview

DOJ Organizational Chart

The Department of Justice Components

LEADERSHIP OFFICES
Office of The Attorney General (AG)   Office of The Deputy Attorney General (DAG)	Office of The Associate Attorney General (ASG)   Office of the Solicitor General (OSG) OSG Organizational Chart
LEADERSHIP SUPPORT
Office of Legal Policy (OLP) OLP Organizational Chart   Office of Legislative Affairs (OLA) OLA Organizational Chart	Office of Public Affairs (PAO) PAO Organizational Chart   Office of Tribal Justice (OTJ) OTJ Organizational Chart
LAW ENFORCEMENT
Federal Bureau of Investigation (FBI) FBI Organizational Chart FBI Field Structure Map   Drug Enforcement Administration (DEA) DEA Organizational Chart DEA Field Structure Map   Executive Office for United States Attorneys (EOUSA) EOUSA Organizational Chart EOUSA Field Structure Map   United States Marshals Service (USMS) USMS Organizational Chart USMS Field Structure Map	INTERPOL Washington - United States National Central Bureau (INTERPOL) INTERPOL Washington Organizational Chart   Criminal Division (CRM) CRM Organizational Chart   Executive Office for Organized Crime Drug Enforcement Task Forces (OCDETF) OCDETF Organizational Chart   Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) ATF Organizational Chart ATF Field Structure Map
STATE AND LOCAL ASSISTANCE
Office of Justice Programs (OJP) OJP Organizational Chart   Office of Community Oriented Policing Services (COPS) COPS Organizational Chart	Community Relations Service (CRS) CRS Organizational Chart CRS Field Structure Map   Office on Violence Against Women (OVW) OVW Organizational Chart
LEGAL REPRESENTATION AND ADVICE
Office of Legal Counsel (OLC) OLC Organizational Chart   Tax Division (TAX) TAX Organizational Chart   Environment and Natural Resources Division (ENRD) ENRD Organizational Chart ENRD Field Structure Map   Antitrust Division (ATR) ATR Organizational Chart ATR Field Structure Map	Civil Division (CIV) CIV Organizational Chart CIV Field Structure Map   Civil Rights Division (CRT) CRT Organizational Chart   National Security Division (NSD) NSD Organizational Chart   Executive Office for United States Trustees (EOUST) EOUST Organizational Chart EOUST Field Structure Map
IMMIGRATION
Executive Office for Immigration Review (EOIR) EOIR Organizational Chart EOIR Field Structure Map
PRISONS
Federal Bureau of Prisons (BOP) BOP Organizational Chart Federal Prison Industries National Institute of Corrections BOP Field Structure Map	Office of the Pardon Attorney (OPA) OPA Organizational Chart   United States Parole Commission (USPC) USPC Organizational Chart
MANAGEMENT AND OVERSIGHT
Justice Management Division (JMD) JMD Organizational Chart   Office of the Inspector General (OIG) OIG Organizational Chart	Office of Professional Responsibility (OPR) OPR Organizational Chart   Professional Responsibility Advisory Office (PRAO) PRAO Organizational Chart
OTHER OFFICES
Foreign Claims Settlement Commission (FCSC) FCSC Organizational Chart	Office of Information Policy (OIP) OIP Organizational Chart

Former Organization, Mission and Functions Manuals can be found in the Department of Justice Archive.

source found here