Funds are requested to subsidize the cost of travel for participants from the United States, Canada, and Mexico (the host country) to a 2-day symposium on The Role of Ni in Biology and Catalysis. The symposium is to be held in conjunction with the Fifth Chemical Congress of North America, on November 11-15, 1997, in Cancun, Mexico. No such conference dedicated to Ni chemistry and biochemistry has been held in the last 15 years. In the interim, the characterization of several Ni-containing proteins and enzymes has resulted in the catalytic chemistry of Ni being examined again in a new light. Catalysis by Ni containing enzymes plays important roles in the biological utilization of hydrogen (hydrogenase), the uptake and use of carbon monoxide (carbon monoxide dehydrogenase) and is essential for the production of methane. Hydrogen and methane are important fuel sources, and carbon monoxide and methane are important pollutant and greenhouse gases. Thus the action of Ni systems has significant ramifications to energy and environmental science, besides Ni being a potential pollutant itself. In regard to the environmental effects of Ni, epidemiological studies have clearly implicated certain Ni compounds as human carcinogens based upon a higher incidence of lung and nasal cancers among Ni refinery workers. The molecular basis for Ni carcinogenesis has also recently come to light. Another area in which Ni chemistry impacts upon health science is in the hydrolysis of urea by urease. The activity of this enzyme has been linked to the virility of Helicobacter pylori, a bacterium that has been associated with gastric ulcers and stomach cancer. Catalysis by Ni compounds (and destruction of catalysis by Ni) also plays important roles in industrial polymerization processes and in petroleum chemistry.