Pi Tau Sigma (PTS)

About PTS

Pi Tau Sigma at Colorado State University

Pi Tau Sigma is an honors society that is so much more than just a resume builder. At Colorado State University, our goal is to is provide students with the hard and soft skills needed to excel in industry. We introduce you to industry professionals and engineering professors that can provide mentoring, advising, and internship/research opportunities. As a member, you will have the opportunity to travel across the country to network with other chapters, their advisors, national board members, and PTS alumni, all while learning leadership skills and making new friends.

Our chapter’s focus is not just to prepare you for your future by helping you get your first job, but to also enhance the engineering community at CSU and in Northern Colorado. We have been involved in many community outreach projects, and are proud to serve Fort Collins in every way possible. Upcoming volunteering opportunities are listed on the volunteering page.


Pi Tau Sigma came into being on March 16, 1915, at the University of Illinois. A similar organization embarked November 15, 1915, at Wisconsin, and other local organizations (such as the Carzeuran of Purdue) were soon to become active.

The early leaders: Professors C. R. Richards, A. C. Willard, and O. A. Leutwiler of the University of Illinois; G. L. Larson of the University of Wisconsin; G. A. Young of Purdue University; and J. V. Martenis of the University of Minnesota, stand out for their early contributions.

In ten years Pi Tau Sigma grew to six chapters in the Midwest (Illinois Alpha, Wisconsin Alpha, Purdue Beta, Minnesota Gamma, Illinois Delta, and Missouri Epsilon). In 1925 the expansion continued to the east with the Penn State Zeta Chapter being installed. Six years later the Texas Kappa Chapter, and the following year the Colorado Mu Chapter established chapters in the south and west. Also in 1932 the expansion continued southeast to Georgia Tech Nu Chapter. It was not until nine years later that the first chapter was installed on the Pacific coast (Oregon State Omega). In twenty-six years Pi Tau Sigma became truly a national honorary mechanical engineering fraternity with a total of twenty-five chapters. During the succeeding four years nine additional chapters were installed.

From 1947 to 1958 forty new chapters were installed. The Chapter-At-Large was established in 1954. By the spring of 1993 the total established chapters had reached one hundred and fifty-three. Earlier, two established chapters in New York merged into one.  At the present, the number of chartered chapters stands at one hundred seventy-four.


Pi Tau Sigma members are chosen on a basis of sound engineering ability, scholarship (upper 25%), personality, and probable future success in their chosen field of Mechanical Engineering. There are three grades of membership: Honorary, Graduate, and Active. Honorary members are technical graduates actively engaged in engineering work; or members of mechanical engineering faculties. Graduate membership is conferred upon persons who would have been eligible had Pi Tau Sigma been established earlier in schools not having chapters, or upon those continuing graduate study. Active members are selected from the junior and senior mechanical engineering classes at their respective schools whose mechanical engineering curriculum must be accredited by ABET.