The twentieth meeting (and our 10th anniversary!) was held January 25-26, 2008, at Xavier University.  We read three papers by Ernst Zermelo (1871-1953) in celebration of the 100th anniversary of his publication of the axioms of set theory and a proof of the axiom of choice. The papers were: Beweis, daß jede Menge wohlgeordnet werden kann, Math. Ann. 59 (1904), no. 4, 514--516 (an English translation of the original text of this paper, part of a letter to Hilbert dated 24 Sep 1904, has the title Proof that every set can be well-ordered, in Jean van Heijenoort's From Frege to Gödel: A Source Book in Mathematical Logic, 1879-1931, Harvard, 1967); Neuer Beweis für die Möglichkeit einer Wohlordnung, Math. Ann. 65 (1907), no. 1, 107--128 (an English translation of this later version of the well-ordering property for sets has the title A new proof of the possibility of a well-ordering, in Jean van Heijenoort's From Frege to Gödel: A Source Book in Mathematical Logic, 1879-1931, Harvard, 1967); and Untersuchungen über die Grundlagen der Mengenlehre. I, Math. Ann. 65 (1908), no. 2, 261--281 (an English version of this paper that lays out the axioms for set theory has the title Investigations in the foundations of set theory. I, also in Jean van Heijenoort's From Frege to Gödel: A Source Book in Mathematical Logic, 1879-1931, Harvard, 1967).