Similarly, some countries offer anonymous caller rejection, which rejects all calls when the subscriber's name, number (or both) is blocked. Some telephone companies protect their clients from receiving calls with blocked information by routing anonymous calls to a service (such as AT&T Privacy Manager), where the caller is required to announce themself. The service then asks the called party if they want to accept or reject the call. Other telephone companies play a recording to the caller advising them of the called party's rejection configuration, and often offer advice (such as prefixing their dialing with *82) on how to get their call to the intended called party. Emergency services will most likely be able to show the restricted number using a service called calling line identification restriction override (CLIRO), or by using general ANI services. These features create a cat-and-mouse game situation,(Wired) whereby subscribers must purchase additional services in order to cancel out other services.
