Geoffrey Heal is Professor of Economics at Columbia Business School. He teaches finance and international business. He is co-founder (with Prof. Graciela Chichilnisky) of the international telecommunications firm Financial Telecommunications (FITEL) . He has held positions at Cambridge, Stanford, Yale, and Princeton, as well as at the University of Sussex, Essex, Paris, and Stockholm. His current research includes the impact of derivative securities on the performance of the economy, behavior of insurance markets, the impact of changing oil prices on the world economy, reform of GATT and development of new approaches to the regulation of international trade, evaluation of environmental risks, regulation of natural monopolies and use of mathematical methods in economics. He has authored numerous works, including Linear Algebra and Linear Economics, Public Policy and the Tax System, The Theory of Economic Planning, Economic Theory and Exhaustible Resources, and The Evolving International Economy. Currently, in conjunction with CITI, he is undertaking a project on Non-Bank Clearing Systems.