Professor Simmens describes himself as a "generalist" applied biostatistician. He has particular interest in applying statistical methods to the social and behavioral components of public health research. As a faculty member, he encourages his students to maintain a generalist perspective regardless of how specialized they become, with an emphasis on combining statistical knowledge, computing, knowledge of the substantive area of research, and problem-solving skills. As a researcher, he collaborates with colleagues in all of the health-related fields, applying his skills to research on HIV, cancer, obesity, mental health, maternal and infant development, chemical and stress-related environmental exposures, and numerous other health issues. As director of the Biostatistics and Epidemiology Consulting Service (BECS), Dr. Simmens oversees a statistical consulting service that provides comprehensive biostatistical support--including data management, biostatistical and epidemiological expertise and grant development--to all faculty at The George Washington University. Dr. Simmens is a Co-core Director of the Clinical and Population Sciences Cores of the DC Center for AIDS Research and Co-lead of the Biostatistics, Epidemiology, and Research Design module of the Clinical and Translational Science Institute at Children's National. Dr. Simmens has been providing consultation services to researchers at GW for nearly 3 decades.