A DNS list should be a provider's personal list of clients she will not see for whatever reason. She can share that information in references to other providers or on some provider only boards, including TER's provider only board. Then it is up to other providers if they want to see this person or not. There are also blacklists of which there are some member (provider) only, and some which are very public and searchable on google. The idea of blacklisting someone should be for serious reasons only. Such as abusive clients, Physical violence, rape, theft, (Not paying for services), and stalking. However there are some providers that will blacklist clients for simple infractions such as "time wasting," sending too many texts or emails, or writing bad reviews. Clients can be outed on these lists revealing their real names, phone numbers, work information etc. Careers and marriages can be ruined. So if you do use a blacklist be very careful what you post there, and make sure the infraction is serious enough that it warrants being blacklisted. Nobody deserves to be outed for "time wasting" or writing harsh reviews, although you have every right to put them on your personal DNS list. However, a rapist, or stalker should be outed. There is kind of an unwritten rule here that we never provide links to blacklist sites. However, you can easily find them on google.