Originally phone sex services consisted of a managed network of dispatchers (live or automated) and erotic performers.
Performers would come to a studio where they received a cubicle, coaching, and cash incentives to keep callers on the line longer.
Leonard convinced magazine owner Carl Ruderman to purchase more of these numbers and the business began to be successful using the magazine to promote the service.
With the progress of technology it became more practical, convenient, and economical for providers to work out of their homes.
Human dispatchers — female, except for gay male phone sex — answered the advertised phone numbers, processed payment via credit card, chose who of the available performers in the dispatcher's judgment best matched the clients' fantasy (grandma, black girl, college girl, etc.), and connected the client with the provider. Either could hang up, though some services put economic pressure on providers not to do so.
Once means of transmitting payment were developed, phone sex turned into primarily a commercial activity, with customers (overwhelmingly male) and sellers (overwhelmingly female).
Due to the potential for emotional intimacy between those who have engaged in phone sex, it is a matter of some debate whether phone sex is to be considered infidelity when involving a person outside of a committed personal relationship.
Nevertheless, phone sex should not be confused with prostitution wherein money is exchanged for real life sexual services or physical interaction.