An exchange between two publishers in which each agrees to run the other’s comparably valued ad at no charge. Value is determined by rate card, placement, size of list, quality of list, name brand fame, etc.

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.