We announce a one-day conference, Set Theory Day on Friday, March 11, 2016, in celebration of the 50th birthday of Prof. Joel David Hamkins. The conference will take place at the CUNY Graduate Center and will last all day, with many of Prof. Hamkins’s former students giving talks on their work. All interested mathematicians are invited to attend. The schedule is posted on nylogic.org/set-theory-day. A PDF program is here.