Sigma Xi, The Scientific Research Honor Society (ΣΞ) is a highly prestigious, non-profit honor society for scientists and engineers. Sigma Xi was founded at Cornell University by a junior faculty member and a small group of graduate students in 1886, making it one of the oldest honor societies. Membership in Sigma Xi is by invitation only, where members nominate others on the basis of their research achievements or potential. Sigma Xi goals aim to honor excellence in scientific investigation and encourage cooperation among researchers in all fields of science and engineering.