Founded in 1902 at the University of Wisconsin-Madison, Alpha Chi Sigma is a professional chemistry fraternity. The Alpha Theta Chapter at the University of Iowa was founded in 1921.

Alpha Chi Sigma has both collegiate and professional chapters throughout the United States consisting of men and women, with more than 69,000 members. The fraternity aims to bring together students and professionals pursuing careers in chemistry, the natural sciences, and health care via outreach, volunteering, and more.