Sister Mary Joseph Dempsey was a Roman Catholic nun and a pioneering figure in the field of medicine. Born in 1856, she became known for her work in nursing and healthcare, particularly in the early 20th century. She was a member of the Sisters of St. Joseph and dedicated her life to serving the sick and needy. Dempsey is best remembered for her contributions to the establishment of the Mayo Clinic in Rochester, Minnesota. She played a crucial role in developing the clinic's nursing program and was instrumental in promoting the importance of compassionate care in medicine. Her legacy continues to inspire healthcare professionals today.