detective agency; private investigation firm
Refers to a business that conducts background checks, investigations, and information gathering, often for corporate or personal matters. Slightly formal; 探偵事務所 is a more common synonym.
Companies sometimes hire a detective agency to conduct background checks before hiring.
He asked a private investigation firm to look into his partner's infidelity.
Suspecting infidelity, she hired a detective agency.
I had a detective agency investigate my fiancé's background.