This volume is the first of two that treat Bernard Lonergan's courses on method at the Gregorian University in Rome between 1959 and 1963. An earlier volume (22), Early Works on Theological Method 1, contains a record of the institutes on method that Lonergan conducted in North America between 1962 and 1968. This volume is presented with the original Latin and an English translation on facing pages. Among the documents featured in Volume 23 are two complete texts written or approved by Lonergan: "Understanding and Method" (1959) and "The Method of Theology" (1962). Also included are Lonergan's own text of a portion of the 1959 course "System and Method," as well as editorial reports on the remainder of that course and on the 1961 revised course on "Understanding and Method." Finally, the book contains an appendix with short materials found in the Lonergan archives relevant to the 1962 course "The Method of Theology."