Used oil handling, as a business, requires an extensive understanding by management that environmental liabilities exist through its supply chain. Findings from a review of the legal requirements of operating a used oil handling business were: understanding the transfer of ownership of used petroleum hydrocarbons is critical to any such business and how this is documented; used oil handlers are responsible for providing training to their staff, including site personnel and any third party waste contractors, and for communicating best practice procedures relating to the management of used petroleum hydrocarbons to all those individuals and organisations involved in business relationships that the used oil handling companies have; used oil handlers should audit the performance of any third party contractors that it engages to conduct work on behalf of its customers. Hypothetical situations of a company planning to enter the used oil handling market are described in relation to petroleum hydrocarbon wastes it handles to illustrate the range of potential liabilities. Companies proposing to establish a used oil handling business should ensure that they provide accurate advice to its employees, its customer's employees and to its third party contractors. all of which may be responsible for handling used petroleum hydrocarbons as part of the service it intends to provide, and that it has a well documented system addressing how environmental issues are managed. (C) 2008 Elsevier B.V. All rights reserved.