In the supply-chain literature, an increasing body of work studies how supp
liers can use incentive schemes such as quantity discounts to influence buy
ers' ordering behaviour, thus reducing the supplier's (and the total supply
chain's) costs. Various functional forms for such incentive schemes have b
een proposed, but a critical assumption always made is that the supplier ha
s full information about the buyer's cost structure. We derive the optimal
quantity discount policy under asymmetric information and compare it to the
situation where the supplier has full information.