Bethel, a Senior Scientist at Lawrence Berkeley National Laboratory, and his team conduct basic and applied research and development on techniques and tools for enabling scientific knowledge discovery in some of the world's largest collections of scientific data generated by computational models, simulations, and experiments. This work lies at the nexus of data management, data analysis, scientific visualization, and high performance computing. Since taking over as Group Leader in 2001, he has grown the program from two persons with an annual budget of about $500K to a vibrant program that has earned an internationally acclaimed reputation for excellence, and that consists of about 12 staff and an annual budget of over $4M. He conceived and was the Coordinating Principal Investigator for the SciDAC Visualization and Analytics Center for Enabling Technology (VACET), which made production-quality, petascale-capable visualization a reality at DOE supercomputing facilities, and has produced software tools in use by a worldwide scientific community in disciplines ranging from high energy physics to climate modeling. His research interests include software architecture, high performance computing, scientific and information visualization, and computer graphics. He is an ACM Distinguished Scientist, and a Senior Fellow at the Berkeley Institute for Data Science (UC Berkeley).