Dr. Suttle is one of the World's leading marine virologists, and is among a small group of researchers credited with launching the field of marine virology. These studies demonstrated that viruses are not only the most abundant and genetically diverse biological entities in the World's oceans, but they are major agents of mortality. The results have had a significant impact on our understanding of nutrient and energy flow in the oceans, and have been a catalyst in the reinvigoration of phage biology and environmental virology. His contributions cross over many fields including biological oceanography, environmental microbiology, microbial ecology, virology and phycology. His active research program encompasses environmental microbiology and virology, but primarily focuses on viruses, their diversity and the roles that they play in the global system. He has active projects examining viruses in extreme environments including high-Arctic ecosystems and the deep sub-surface, as well as studies of natural reservoirs of viral pathogens, the use of viruses as environmental proxies, the isolation and characterization of unusual viruses, the evolution and diversity of viruses and viral communities, and viruses as proxies for life on other planets