Dr. Alonso was born in Argentina where he attended medical school and received his M.D. degree from the University of Cuyo in 1962. After two years of training in general surgery there, he moved to the United States to become an intern in surgery at Bellevue Hospital, New York City. This was followed by a residency in Anatomic Pathology at The New York Hospital-Cornell Medical Center. Upon completion of his residency in 1969, Dr. Alonso joined the faculty of Cornell University Medical College as an Instructor in Pathology. He rose through the ranks and became a full Professor in 1984.
During his years as a Pathology faculty member, Dr. Alonso did research in cardiovascular diseases, practiced Anatomic Pathology, directed the second year Pathology course, introduced the use of computers and digital images in medical student education, and pioneered the use of problem-based learning.
Dr. Alonso joined the Medical College administration in 1982 as Associate Dean of Admissions. Five years later he was appointed Senior Associate Dean for Academic Affairs, a newly created position that oversaw all aspects of the medical education mission. In this capacity, his areas of responsibility included the educational program leading to the M.D. degree and all related offices (Academic Affairs, Curriculum and Educational Development, Admissions, Student Affairs, Weill Education Center, Minority Affairs, Student Financial Aid) and the Office of Continuing Medical Education. Later, the Program in Gross Anatomy (when it was split from the Department of Cell Biology and Anatomy), and the Physician Assistant Program were added to his responsibilities.
During the mid 90's, Dr. Alonso directed a major curricular reform at the Medical College that resulted in the creation of a very successful curriculum characterized by integration of the teaching of basic and clinical sciences, problem-based learning, office-based preceptorships, and primary-care and doctoring courses. Implementation of this new curriculum began in the fall of 1996 coinciding with the opening of the Weill Education Center, a new teaching facility designed under his supervision. Implementation was completed four years later with the graduation of the class of 2000.
Dr. Alonso served as the first Dean of Weill Cornell Medicine - Qatar from 2001 to 2008. Starting January 1, 2009, he became Dean Emeritus by appointment of the Board of Overseers of Weill Cornell Medical College.