In many developing countries and economies in transition, past government interventions in commodity markets have reduced the economic returns to private storage or obviated the need for private credit. But with the opening of markets and the liberalization of trade, such instruments as warehouse receipts are becoming important in the transition to well-functioning markets. Warehouse receipts have a long history in industrial countries – a short one in developing countries. The receipts, also called warrants, are documents stating the ownership of a specific amount of a commodity or good with specific characteristics stored in a specific warehouse for a specific fee. When backed by provisions that enhance their value as collateral, warehouse receipts can play an essential role in agricultural marketing. They can be traded, sold, swapped, or used for delivery against a derivative instrument, such as a futures contract. The overall efficiency of agricultural markets is thus greatly enhanced by the ability to convert agricultural products into such tradable devices.