Dr. Willey was involved in the planning and design of the Zucker School of Medicine and held a joint appointment between the Department of Biology in the Hofstra College of Arts and Sciences and the Science Education Department at the School of Medicine from 2009-2013. In September of 2013, she joined the Department of Science Education full time and assumed the position of Chair in 2014. In 2017, she was installed as the Leo A. Guthart Professor of Biomedical Science. In addition to her role as Department Chair, Dr. Willey also serves as course director for Human-Microbe Interactions, taken by all second-year medical students.

For over 20 years, Dr. Willey's research focused on the filamentous soil bacteria, Streptomyces. In addition to antineoplastic and immune modulatory agents, these microbes produce most of the antibiotics currently used in human and veterinary medicine. Her lab explored the processes and molecules that govern morphological and physiological differentiation in this group of bacteria. Her discovery of a lantibiotic peptide with biosurfactant activity was first such peptide noted to have a function other than that of antibiotic and has transformed the search for this class of natural products and their potential medical and industrial applications.

Dr. Willey came to Hofstra after completing a Postdoctoral Fellowship at Harvard University in the laboratory of Professor Richard Losick in the Department of Molecular and Cellular Biology. She earned her Ph.D. in 1988 from the Massachusetts Institute of Technology in Microbiology in partnership with the Woods Hole Oceanographic Institute. She was awarded a B.A. in Biology from the University of Pennsylvania in 1981 and in 1978 she graduated from the last class of the Hospital of University of Pennsylvania's Nursing Diploma program. She worked as staff nurse while earning her B.A. at Penn.

Within higher education, Dr. Willey's commitment to education is exemplified by the approximately 70 undergraduates she mentored in her laboratory as well as master's students and postdoctoral fellows. In 2004 she assumed lead authorship of the majors' textbook Prescott's Microbiology and has since published eight editions. This text is published by McGraw-Hill Higher Education and is translated into five languages.