- 4-H Programs - Providing a variety of programs for youth of all ages.
- ESCC 911 (non-emergency) - Providing the first response to all citizens, getting the right people to the right place at the right time.
- Auditor's Office - Auditing, financial records, payroll, budget preparation, levies, apportioning, tax collection, passports, elections, and voting.
- Board of Commissioners - The governing body of Pennington County.
- Buildings & Grounds Department - Responsible for operations and maintenance of all County facilities as well as coordination, planning and construction of new facilities.
- Emergency Management Department - The local government agency charged with coordinating the initial response to disasters and emergencies in the Pennington County area.
- Equalization Department - The function of the office of the Equalization Office is to annually assess all taxable real property in Pennington County for property tax purposes.
- Fire Administration Department - Providing a variety of services to Pennington County volunteer Firefighters and serving as a liaison between various local, state, and national law enforcement and fire agencies
- Human Services Department - Providing emergency assistance for individuals who meet the eligibility criteria as outlined in the Pennington County-approved guidelines and state statutes.
- Veterans Services - Assisting veterans and their dependents and survivors in applying for veterans' benefits including benefits from the Department of Veterans Affairs and the State of South Dakota.
- Highway Department - Responsible for routine repair and maintenance of 836 miles of road and 128 bridges, including snow removal operations and major reconstruction projects.
- Human Resources Department - Functions as the centralized job applicaton agent for all Pennington County Departments.
- Information Technology Department - Providing a variety of services to County Departments to support the business needs of Pennington County.
- Planning Department - Maintaining and enforcing planning, zoning, building permits, and ordinances within Pennington County.
- Ordinance Enforcement - Implementing procedures for the enforcement of Pennington County ordinances.
- Public Defender's Office - Representing all indigent persons who by law are entitled to be represented by an attorney in the proceeding in which they are involved.
- Register of Deeds Office - The Register of Deeds Office keeps full and true computerized, filmed and scanned records of deeds, mortgages and other instruments authorized by law to be recorded.
- Sheriff's Office - Serving and protecting the citizens of Pennington County.
- City/County Alcohol & Drug Programs - Providing a full continuum of services for adults and families allicted with substance use disordrs and/or mental health conditions.
- Jail - Maintaining an adult corrections facility that preserves human rights and dignity.
- Juvenile Services Center - Providing a safe environment for juveniles in custody in the Pennington County area.
- Law Enforcement - Providing law enforcement, patrol, transport security, warrants school liaison, and coroner services.
- State's Attorney Office - Serving as the chief prosecutor of adult and juvenile crimes in Pennington County.
- Juvenile Diversion - A collaborative program which includes Teen Court and Truancy Intervention Program offering an alternative to court involvement for juvenile offenders ages 10-17.
- Victims Assistance - Ensuring that crime victims receive the rights to which they are entitled, including advocacy to help them recover from the trauma of their victimization.
- Treasurer's Office - Responsible for collecting taxes for real estate and mobile homes, issuing titles and license plates, issuing distress warrants, and remitting payments to the State of South Dakota.
- Weed and Pest Department - Conducting and managing a sound, integrated weed & pest management program within Pennington County.