After receiving her B.A.from Yale College she stayed on at Yale for a masters degree in English and a Ph.D. in American Studies. She taught American Studies and English at the University of Texas from 1985 to 2003, and was Chair of the Department of American Studies. .She has been awarded an American Council of Learned Societies Fellowship, was a Fulbright Distinguished Lecturer in Japan and was the winner of a Harry H. Ransom Teaching Excellence Award at the University of Texas. Much of her work is focused on Mark Twain but she has also published works on writers such as Frederick Douglas and Theodore Dreiser. Her research interests have lead her to focus on the influence of African American voices on American literature. Dr. Fishkin is the author, editor or co-editor of over forty books and has published over eighty articles and reviews. Her book Was Huck Black? Mark Twain and African-American Voices was selected as an "Outstanding Academic Book" by Choice in 1993.