The Auxiliary to the Isabella McCosh Infirmary has played a key role in furthering the growth and quality of health care provided at Princeton's University Health Services for more than a century. UHS is grateful for the Auxiliary's leadership in keeping health and well-being central to the Princeton University mission and student experience.

The first University infirmary, built in 1892, was named in honor of Isabella Guthrie McCosh , wife of President James McCosh.

The Ladies Auxiliary, as it was then known, was founded on June 2, 1902 as a group of 15 women charged with furnishing designated rooms for women in the new gymnasium. After completing this task, these enterprising women extended their work to matters pertaining to the infirmary. In response to the need for better infirmary facilities, the Auxiliary quickly expanded its membership of 15 to 100, and committed funds to the infirmary. In 1904, the Auxiliary amended its name to the Ladies Auxiliary of the Isabella McCosh Infirmary and, by 1910, had funded additional nursing and maintenance personnel, new patient rooms, solaria, and bedrooms for nurses and housekeepers. In addition to making these physical improvements possible, the Auxiliary created an emergency fund for students in need, a general fund, and a fund for the salary of the infirmary's first Medical Director. In 1919, once again responding to requests for more adequate space in which to care for patients, upon their own initiative, the Auxiliary, hired an architect to produce designs and cost estimates for a new Infirmary building. The dedicated women of the Auxiliary raised over $340,000 to finance the new infirmary, completed in l925. Of 1500 donors to the building fund, over 1300 were women. Although women were not admitted as students to the University until 1969, they nonetheless played an extremely influential role in its affairs and the welfare of its students for decades prior to that decisive time in Princeton 's history.

The Ladies Auxiliary has been considered by many as "the heaven of society" and their support a "godsend." Although their regular contributions continued to be a source of support for the infirmary and the students at Princeton University , their extraordinary influence was not only financial. The caring and devoted members of Auxiliary also provided personal care and attention to students during epidemics and to the military troops residing at the infirmary during wartime.

The Auxiliary's commitment to the infirmary and steadfast ability to effect change proved essential to the development of the modern-day University Health Services. Throughout the years, the Auxiliary has responded to UHS' many new and challenging needs. Special endowments and funds were developed to support operating costs, laboratory expenses, repairs and improvements, students with financial need, and unanticipated requirements of the infirmary. Their presence is marked permanently in the building; the Margaret S. Goheen Medical Library was dedicated in 1989 and the Janet C. Morgan Health and Wellness Library was dedicated in 2004. In keeping with the times, the organization changed its name in 2001 to "The Auxiliary to the Isabella McCosh Infirmary." After being known as the "Ladies Auxiliary." for 100 years, the group wished to make the group more inclusive and encourage a broader membership.

UHS remains indebted to the Auxiliary for advocating for the health and well-being of all Princeton students and for its continuous, generous, gracious, and sympathetic care for the students and the UHS staff.