Private police or special police are types of law enforcement agencies owned and/or controlled by non-government entities. Additionally, the term can refer to an off-duty police officer while working for a private entity, providing security, or otherwise performing law enforcement-related services. Officers engaging in private police work have the power to enforce the law. However, the specific authority they have, and the terms used for it, vary from one place to another.

In jurisdictions that allow private police, private police may be employed and paid for by a non-governmental agency, such as a railroads, ports, campuses, nuclear facilities, and hospitals and other "special police" but they are peace officers or law enforcement officers who are commissioned, licensed, and regulated by the state. They are required to swear an oath to uphold the laws of the state where they are commissioned and follow the same regulations peace officers / law enforcement officers must abide by. The main difference between a private police officer and a regular police officer is who is signing their paycheck and their jurisdiction.

Many people confuse private police with security guards. Security officers are regulated by the state, but generally do not have police powers, such as the ability to arrest on a warrant, or issue citations and summons for misdemeanor offenses. In contrast, most private police are sworn police officers employed by private entities, or even small governmental departments (such as library police, etc.).

Even though private police departments receive their commissions from the government, they are generally not considered government actors.

Private military companies providing law enforcement services may be referred to as private gendarmeries or private civil guards, due to their more militarized nature.

Private police (also called company police) are commissioned police officers that are hired by a non-governmental agency, such as a university, hospital, port, nuclear facility, railroad, etc. These police officers swear an oath to the state or country (or both) they are commissioned in but are paid for by the private organization that hired them. Depending on the jurisdiction, they may have full police power within their jurisdictions or limited police powers. Private police officers are held to the same regulations and standards as regular police officers. Sometimes (but not all times) these officers are commissioned as "special police," the special-term delineating their narrow jurisdiction.

In some countries, like the United States, the term "special police" indicates a police force that has limited law enforcement powers. Special police may be employed by either a governmental agency or a non-governmental agency, and as such are not always private police.

Some states give local officials the ability to appoint special police officers with specific duties, either to assist local law enforcement or to provide assistance during an emergency. These officers may or may not be commissioned police officers, but generally have the same privileges and immunities as police officers. For example, some municipalities appoint special police as security for the municipal buildings and airports, freeing up commissioned police officers for general police duties. Special Police officers can be public officers (such as the WMATA Special Police in DC), or private officers, (such as the Metro Special Police Department's Special Police Officers).