Dr. Elizabeth Szybalski, long-time scientist at the McArdle Laboratory for Cancer Research, passed away on Thursday, April 23, 2015 after a long illness. She was 87 years old. Elizabeth was born and raised in Philadelphia, Pennsylvania, the daughter of Mabel H. Hunter and historic Orphan-Court Justice, the Honorable David G. Hunter. She showed a strong intellect and a keen interest in science even as a young girl. After receiving a BS degree in physics from Duke University, Elizabeth went on to earn MS and PhD degrees in microbiology at the University of Pennsylvania at a time when there were very few women in science. Elizabeth met her future husband, Dr. Waclaw Szybalski, at Cold Spring Harbor Laboratory in 1952. They were married in 1955. She worked as a microbiologist at the University of Pennsylvania and in industry for several years before moving to Madison in 1960 with her husband. For over 25 years Elizabeth and Waclaw worked together, carrying out ground-breaking research in genetics and molecular biology at the McArdle Laboratory for Cancer Research. Her major contributions were toward creating the new field of gene therapy by performing the first-ever transfection (genetic transformation) of human cells, and developing a means of selecting for cells transfected with the human HPRT gene (encoding HPRT, also abbreviated as IMPPase) using “HAT” selection media, designed and named HAT by Elizabeth. This became a commonplace method for introducing genes of interest into genomes of mammalian cells. Among her other major contributions was the physical mapping of the bacterial (Escherichia coli) bio operon by electron microscopy. Elizabeth is survived by her husband Waclaw and her children Barbara (Larry) Hunter-Sandor and Stefan Hunter Szybalski.