In Volume I Larry Teaches Opener's bid and the responses using 21st century methods (including 2/1 Game Forcing).
In Volume II Larry Teaches the most important bid of the auction--Opener's Rebid. Modern 21st century approach throughout.
In Volume III Larry Teaches the 4th bid of the auction (Responder's Rebid) and competitive auctions (both sides in the bidding).
All concepts explain modern 21st century bidding in easy to follow style with numerous examples and quizzes.
These books are based on his popular 2017-2021 ACBL series -- but with new and enhanced material and extra quiz questions.
For newer players or for more experienced players who wish to review the basics.78, 68 and 79 pages (large size, spiral bound).
If you really want to improve your bidding and get to the right contract, these books are your best resource.
Even though I have a 3 inch binder with all of Larry's Modern Bidding articles from the ACBL Bridge Bulletin from January 2017 - November 2020, I immediately ordered all 3 of these volumes as soon as I found out they were available.
I am only up to the 2 Club opening in Volume 1 but I am really learning some of the finer points of the opening 1 bids. Larry explains things very clearly and also points out bids that are not considered to be standard and paying attention to your rebids before you open.
Added a few days later: I finished Modern Bidding Vol I. It was great. Just started reading Vol II. Agree that these are essential reading for the serious bridge player.