Susan Willavize received her Ph.D. in biostatistics from The Ohio State University. Her first position was as a statistician at Procter and Gamble Pharmaceuticals (Norwich, NY) where she supported all phases of clinical trials for a wide range of compounds and also consulted on preclinical and manufacturing statistics. She joined Pfizer Central Research (Groton, CT) in 1992 where she has held management and technical roles providing statistical support for clinical pharmacology studies. Since 2004, she has provided technical support for pharmacometrics and pharmacokinetic/pharmacodynamic modeling and simulation. She is the co-author of 25 peer reviewed papers reporting the results of clinical trials and two papers on statistical methods research. Her interest in dose-response modeling for combination drugs developed during her recent graduate studies in pharmacokinetics and pharmacodynamics in the Pharmaceutical Sciences Department at the University at Buffalo (NY).