Tim Polk joined NIST in 1982, and joined the computer security division in 1989. Polk contributed to the development of numerous IETF PKI standards as an Author, Reviewer and Working Group Co-Chair. Polk also served four years as a Security Area Director on the IETF’s IESG. He became the NIST Cryptographic Technology Group Leader in 2011. Polk joined the Office of Science and Technology Policy in 2012, acting as Assistant Director for Cybersecurity until 2017. Since returning to NIST, Polk has split his time between the National Cybersecurity Center of Excellence and Commerce Department’s work on resiliency against botnets and related threats. Polk is also Co-Author of the book Planning for PKI. He has degrees in computer science and electrical engineering from the University of Maryland.