Scott Williamson (1975-2008) was an accomplished early-career researcher who worked in theoretical population genetics and evolutionary modeling. A humble, kind, and well-liked scientist, Scott made significant theory contributions to understanding the dynamics of natural selection in populations. His work employed several modeling traditions, including coalescent theory, Poisson random fields, and sequence substitution models. He also applied insights from statistical population genetics to study selection from genetic sequences in many different organisms, including Drosophila, humans, rice, and HIV. A native of Kansas, Scott received both his undergraduate and graduate degrees at the University of Kansas. Shortly after starting a faculty position at Cornell University, Scott passed away from brain cancer.