Sigma Theta Tau is a national honor society of nursing founded in 1922. Its purposes are to: recognize superior achievement, recognize the development of leadership qualities, foster high professional standards, encourage creative work; and strengthen commitment to the goals and purposes of the nursing profession.

Membership in Sigma Theta Tau is an honor conferred through affiliated chapters on students in baccalaureate and graduate programs who have demonstrated excellence in their nursing programs. Graduates of baccalaureate programs who demonstrate excellence in leadership positions in nursing also are eligible for membership.

Benefits of membership include educational programs offered at the state and national levels, state and national newsletters, and the opportunity to participate in an organization of professional nurses. The society promotes a national reward system for contributions to nursing scholarship, creativity, and commitment to nursing.

For several years faculty of Montana State University's School of Nursing discussed the possibility of organizing a chapter of Sigma Theta Tau. Alpha Tau Delta, not a chapter of Sigma Theta Tau, had been a society for undergraduate nursing students but it did not meet Sigma Theta Tau's requirement of an honor society and excluded faculty. Student interest in Alpha Tau Delta waned and it was subsequently dissolved. In 1975, following reorganization of the governing structure of the School of Nursing, several doctorally-prepared people joined the nursing faculty, which provided the potential for development of a scholarly community interested in the advancement of nursing research. Three years later, in 1978, the Research Committee of the MSU nursing faculty initiated plans to become associated with Sigma Theta Tau.

Montana's Zeta Upsilon Chapter was chartered in 1982. It is unique within the structure of Sigma Theta Tau because it is a statewide chapter established by the two baccalaureate nursing programs in the state, Montana State University (MSU) College of Nursing, Bozeman, and Carroll College, Helena. In most instances a chapter is established in a single educational unit, which is an integral part of a college or university and which grants a baccalaureate or higher degree for completion of the nursing program.

A planning meeting was held in December 1978 and members of the MSU Research Committee communicated with the Executive Director of Sigma Theta Tau about forming a Montana Honor Society of Nursing (MHSON). Results of a survey of faculty gave strong support in favor of starting a chapter. There was interest in including all nurses in the state who might meet the membership requirements into one organization and so the possibility of a statewide chapter was explored. On April 20, 1979, the chairman of the MSU Research Committee recommended that MSU nursing faculty join with Carroll College nursing faculty to become an honor society at-large for Montana. A meeting of the combined group took place on June 9, 1979. Officers were elected, annual dues of $20 a year were set, and committees were appointed. The first formal induction ceremony was held at Carroll College in Helena on May 2, 1980. The sixteen formally-inducted members included nursing students and alumni-community leaders. Fifty-four new members were inducted at the second formal ceremony held at MSU in Bozeman on June 6, 1980. A major goal of the MHSON was acceptance by Sigma Theta Tau as a statewide chapter, which was approved at a national convention in the autumn of 1981 and named Zeta Upsilon. Induction into the new chapter took place on June 2, 1982. Similar inductions have taken place twice a year, one at each campus.