Primarily, we should note that there are no international laws that regulate debt collection. In other words, none of the countries has adopted special documents that establish rules for international debt collection activities and prohibit actions against the debtors.
So, are there any legislative acts that regulate the international debt recovery?
Yes, the laws of the country, where the debtor is located, are applied for activities of international debt collection agencies. This is the reason why most international companies choose local representatives for entrustment of debt collection claims.
Not only substantive law but also the procedures of the debt collection regulates by domestic legislation. For example, laws of each particular country set particular requirements to the document that serves as proof of the debt collector's authority to collect the outstanding amount.
However, you should remember that generally there are common rules on how the debtor must be treated in every country. Such actions like threats of violence, late and weekend calls are strictly prohibited and may cause even criminal prosecution for such agencies.