In 1867, Clark became the third president of the Massachusetts Agricultural College (MAC), now the University of Massachusetts Amherst. He was the first to appoint a faculty and admit a class of students. Although initially successful, MAC was criticized by politicians and newspaper editors who felt it was a waste of funding in a state that was growing increasingly industrial. Farmers of western Massachusetts were slow to support the college. Despite these obstacles, Clark's success in organizing an innovative academic institution earned him international attention.