The process in which a publisher or advertiser pays a list owner to send its messages to that list. Usually involves the list owner sending the message’s on the advertiser’s behalf. (If someone hands over their list to you, beware.)

3 Quick And Easy Ways To Build A Profitable Opt-In List
You finally realize that you need a good opt-in list. After reading countless articles and sought expert advices and have read many success stories of people creating a small fortune with opt-in lists you finally decide to have one of your own.