In buy-back, the seller agrees to purchase goods and services from the buyer up to an agreed percentage of his deliveries, the object of primary transaction being machinery, equipment patents, know-how or technical assistance that will be used to set up production facilities for the buyer. The parties agree that the seller will subsequently buy from the buyer products produced in those production facilities. As in counterpurchase, both flows of products are paid for in money, and the value of the products bought back may be lower than, equal to or higher than that of the products of the primary transaction. Inexperience can produce exploitative agreements.