Telephone readings are live readings where both psychic and client hear each other by connecting via premium rate telephone line. In the last years, with restrictions on premium rate numbers, more common are pre-paid callbacks, in which case client leaves his/her credit card details over the phone to an operator, after which gets a call on a specified phone number. Telephone readings became most popular with the growth of live advice TV shows as main means of advertising, and is commonly used by companies rather than individual psychics, due to high setup costs.