Alexander V. Karasev received his PhD in virology from Moscow State University in Russia. After moving to the United States in 1992, he worked on plant virus problems in California, Florida, and Pennsylvania. Since joining the University of Idaho in 2006, Karasev has developed a research program in plant virology focused on viruses of potato in the Pacific Northwest. A major emphasis of this research is on Potato virus Y (PVY), a main virus affecting the potato industry. Karasev’s research during the past 13 years has focused on understanding interactions between plant viruses and their hosts and how resistance genes are driving virus evolution. He has characterized local and global PVY populations, revealing a close link between shifts in virus strain composition in the field and introductions of new, strain-specific resistance genes in newly released potato cultivars. His current efforts are focused on identifying new sources of resistance to PVY and other potato viruses.