The international honor society of science and engineering, Sigma Xi (Xi is pronounced with a "Z" sound--Sigma "Zi"--as in "xylophone) has nearly 65,000 members who were elected to membership based on their research potential or achievements. More than 500 Sigma Xi chapters in North America and around the world provide a supportive environment for interdisciplinary research at colleges and universities, industry research centers and government laboratories. Nearly 200 members have won the Nobel Prize.