Recital 42

Other forms of direct marketing that are more costly for the sender and impose no financial costs on subscribers and users, such as person-to-person voice telephony calls, may justify the maintenance of a system giving subscribers or users the possibility to indicate that they do not want to receive such calls. Nevertheless, in order not to decrease existing levels of privacy protection, Member States should be entitled to uphold national systems, only allowing such calls to subscribers and users who have given their prior consent.