Pay per sale

Unique identifiers, which can be stored in cookies or included in the URL, are used to track the movement of the prospective buyer to ensure that all such sales are attributed to the advertisement in question.

[2] In these cases, a cookie-based rotating system of telephone numbers can be used to accurately trace a phone call to the source online visitor.

The business model means that merchants no longer bear the cost of "pay-per-click"; instead, the "pay-per-sale" provider takes on the risk of conversion.

[4] The industry has four core players: the merchant (also known as retailer or brand), the network, the publisher (also known as 'the affiliate'), and the customer.

[5] However, there is typically an upfront set-up fee, as well as monthly minimum charges for the advertiser, in addition to relatively stringent requirements around entry into the network to begin with.