The Art Loss Register (ALR) is the international due diligence service used by the art trade. Its database includes 500,000 items that have been registered as lost, stolen, subject to a legal dispute or lien, or with reported issues of authenticity. Since 1990, the ALR has offered its services to law enforcement, auction houses, dealers, museums, and collectors to check items moving publicly and privately through the international art market, and now carries out 400,000 such checks each year. Its searching services are also incorporated into the vetting at TEFAF in New York and Maastricht (find out more here), as well as other major fairs.