High Quality Content by WIKIPEDIA articles! Overselling or Overbooking refers to the selling of a volatile good or service in excess of actual capacity. Overselling is a common practice in the travel and lodging industry. In telecommunications, sometimes the term oversubscription is preferred. The practice occurs as an intentional business strategy where sellers expect that some buyers will not consume all of the resources they are entitled to, or that some buyers will cancel, the practice of overselling ensures that 100% of available supply will be used resulting in the maximum return on investment.