"Controlled transaction" refers to the practice of allowing illegal or suspicious goods to be transported out, through or into the territory of one or more countries with the knowledge and monitoring of the competent authorities, with the purpose of detecting crimes and identifying the people involved in them.

Controlleddelivery refers to the investigation method that the investigation organ can't catch the crime on the spot, but comprehensively monitor it, let it continue to be implemented under supervision, and then catch other suspects when the crime touches them. This investigation method is often used in drug and smuggling cases.