Virginia Litwin is a Principal Scientist at Covance Central Laboratory Services. After numerous years in the pharmaceutical/biotechnology industry, she has become a leader in the application and validation of flow cytometric methods in drug discovery and development. She founded the Flow Cytometry Subcommittee of the Ligand Binding Assay Bioanalytical Focus Group within the American Association of Pharmaceutical Scientists (AAPS). She is an active contributor to the International Clinical Cytometry Society (ICCS) and the International Society for Analytical Cytology (ISAC). She received her bachelor's from the University of California and her doctorate from the University of Iowa. Philip Marder was internationally distinguished for his leadership in the application of flow cytometry in early drug discovery and development. He was a key contributor to the scientific community as an active member of ISAC and AAPS. After receiving both his bachelor's and master's degrees from The Ohio State University, he had a distinguished thirty year career at Eli Lilly and Company.