A background check or background investigation is the process of looking up and compiling criminal records, commercial records and financial records (in certain instances such as employment screening) of an individual.

Background checks are often requested by employers on job candidates, especially on candidates seeking a position that requires high security or a position of trust, such as in a school, hospital, financial institution, airport, and government. These checks are traditionally administered by a government agency for a nominal fee, but can also be administered by private companies. Results of a background check typically include past employment verification, credit score, and criminal history.

These checks are often used by employers as a means of objectively evaluating a job candidate's qualifications, character, fitness, and to identify potential hiring risks for safety and security reasons. Background check is also used to thoroughly investigate potential government employees in order to be given a security clearance. However, these checks may sometimes be used for illegal purposes, such as unlawful discrimination (or employment discrimination), identity theft,