Michael O'Sullivan, M.D., a former member of the Mayo Clinic Board of Governors, CEO of Mayo Clinic in Arizona, and the founding medical director of Mayo Medical Laboratories (now Mayo Clinic Laboratories) and Mayo Clinic Health System, passed away on April 20. He is remembered for his inspirational leadership as well as for his warmth and hospitality.

"Dr. O’Sullivan was a true icon who lived out Mayo Clinic’s values,” says Gianrico Farrugia, M.D., president and CEO of Mayo Clinic. "He dedicated his life’s work to Mayo Clinic and our patients, and his impact lives on in the work we do to transform healthcare today.”

Michael B. O'Sullivan was born Aug. 20, 1935, in Tralee, County Kerry, Ireland. He received his medical degree from University College, Cork, Ireland, and began his postgraduate studies in Buffalo, New York. After serving as a captain in the U.S. Air Force, Dr. O'Sullivan and his wife, Margaret, moved to Rochester, where he began a fellowship in Hematology and Pathology at Mayo Clinic. He joined the staff as a consultant in Hematopathology in 1969.

Pioneer in laboratory services

Shortly after arriving at Mayo Clinic, Dr. O'Sullivan was asked to establish what would become Mayo Clinic Laboratories.

Mayo Regional Laboratory, fittingly founded on St. Patrick's Day in 1971, initially served four regional hospitals that did not have pathology services. Over time, that project evolved into Mayo Medical Laboratories and, later, Mayo Clinic Laboratories.

Dr. O'Sullivan also served as chair of the Department of Laboratory Medicine and Pathology for more than a decade. His early leadership experiences prepared him for instrumental roles that would help expand Mayo Clinic's presence throughout the Midwest and beyond.

"Both Mayo Clinic Laboratories and Mayo Clinic Health System were founded through his vision, and their ongoing successes are testaments to what he has done for each and every one of us and the patients we serve," says William Morice II, M.D., Ph.D., president and CEO of Mayo Collaborative Services.

Developing Mayo Clinic Health System, leading Mayo Clinic in Arizona

Dr. O'Sullivan was Mayo Clinic Health System's first physician leader. Under his guidance, multiple physician-led community clinics and hospitals across Minnesota, Wisconsin and Iowa joined Mayo Clinic Health System beginning in 1992.

"Dr. O'Sullivan's visionary leadership and foresight were instrumental in shaping the organization we are today," says Prathibha Varkey, M.B.B.S., president of Mayo Clinic Health System. "We are incredibly grateful for his legacy, which continues to guide our mission."

In 1997, Dr. O'Sullivan was named CEO of Mayo Clinic in Arizona. It was a challenging time for the organization, which was facing many financial tests. Dr. O'Sullivan was a stabilizing force, leading the practice to success in a highly competitive market and overseeing the opening of Mayo Clinic Hospital in Phoenix before retiring in 2002.

"Dr. O'Sullivan's leadership was truly inspiring," says Richard Helmers, M.D., now regional vice president of Mayo Clinic Health System in Wisconsin, who served as chair of the Division of Pulmonary Medicine and vice chair of the Clinical Practice Committee in Arizona during Dr. O'Sullivan's tenure as CEO. "His dedication and passion were contagious, and he served as a constant role model for me."

Dr. O'Sullivan's contributions were also recognized by the patients he cared for. In 2000, benefactors Charles and Rowena Simberg established the Michael B. O'Sullivan, M.D., Award for Excellence in Clinical Nursing in his honor, which recognizes outstanding contributions by registered nurses in Arizona.

The art of medicine — and life

Dr. O'Sullivan's well-known love of music inspired him to establish the Mayo Clinic Center for Humanities in Medicine in Arizona. He also established Mayo Clinic talent shows and frequently hosted dinners for staff at his home.

Dr. O'Sullivan's genuine affection for the people in his life was evidenced through his hospitality as well as through regular daily interactions.

"Mike was a warm, kind and caring man," Curtis Hanson, M.D., currently chief medical officer and executive vice president of Mayo Clinic Laboratories and prior chair of the Department of Laboratory Medicine and Pathology and Mayo Collaborative Services. "He always wanted to know how you were doing and how your family was. He had this way about him where you just wanted to talk to him and listen to what he shared back with you. His eyes would twinkle, and there was always a story that would follow. I will always be grateful to Mike for what he brought to Mayo and for how he cared about everyone around him."

Following his retirement, as an emeritus staff member in the Department of Laboratory Medicine and Pathology, Dr. O'Sullivan contributed to special projects for Mayo Clinic and spent time with family and friends at home on Spider Lake near Hayward, Wisconsin.  

"The real legacy of Dr. O'Sullivan is what a wonderful man and physician he was," Dr. Morice says. "Humble, caring, energetic and full of wit and humor. He will be dearly missed."

Celebration of life

Mayo Clinic will hold a celebration for the life of Dr. O'Sullivan on Saturday, April 27, from 11 a.m. to noon CDT. You can join the service here.

Related Articles