The Nobel Prize was awarded in Physiology or Medicine in 1998 to Louis J. Ignarro, Robert F. Furchgott and Ferid Murad for demonstrating the signaling properties of nitric oxide. Nitric oxide (NO) is one of the few gaseous signaling molecules and is a key biological messenger that plays a role in many biological processes. NO research has led to new treatments for treating heart as well as lung diseases, shock and impotence. (Sildenafil, popularly known by the trade name Viagra, enhances signaling through NO pathways.) Scientists are currently testing whether NO can be used to stop the growth of cancerous tumors, since the gas can induce programmed cell death, apoptosis. This is another “must-have? volume packed with robust methods from authors around the globe. Researchers interested in the detailed biochemistry of NO and its synthesis will have this indispensable volume on their shelves.