Nearly all administrative agencies can be characterized as social welfare, regulatory, or public service. Social welfare agencies are responsible for promoting the general welfare of the people. This mission often includes providing services or cash distributions to persons who qualify for assistance. Regulatory agencies are responsible for proscribing or requiring certain behavior, determining compliance with the law, and prosecuting (and occasionally punishing) those who violate the law.

Regulatory agencies possess a wide range of authority. Many control licensing. Regulatory agencies also set rates for certain industries. The third type of agency is the public service agency. A public service agency is not involved with the redistribution of money, nor does it regulate. An agency may also be characterized as either an executive agency or an independent agency. Executive agencies are organs of the executive branch.

Other agencies are referred to as independent because the president exerts less control over them. These agencies are often headed by a group of individuals, and usually are referred to as a board or commission.