Consists of those who have formerly had relations with the marketing organization, typically through a previous purchase, but have not purchased from the marketer within a certain timeframe.
Those who have yet to purchase but possess what the marketer believes are the requirements to eventually become a customer.
Those who hold the potential to undertake activities offering long-term value to an organization that not only includes purchasing products but also providing additional support for the marketer (e.g., offer feedback, act as word-of-mouth advertisers)