This volume is the result of a state-of-the-art symposium on biotechnology of anaerobic microbes, in honor of Professor Lars G. Ljungdahl on the occasion of his retirement and 80th birthday. The volume presents current work on the use of anaerobes for biomass conversion, cellulose degradation, and processes to produce alternative biofuels, such as ethanol and biodiesel. NOTE: Annals volumes are available for sale as individual books or as a journal. For information on institutional journal subscriptions, please visit www.blackwellpublishing.com/nyas. ACADEMY MEMBERS: Please contact the New York Academy of Sciences directly to place your order (www.nyas.org). Members of the New York Academy of Science receive full-text access to the Annals online and discounts on print volumes. Please visit www.nyas.org/membership/main.asp for more information about becoming a member.