Last updated in September 2020, current as of January 2024. Printed in Color. An up-to-date printed copy of this publication may be used to meet the 'copy of these Rules' requirement of 33 CFR 83.01(g) or Inland Rule 1(g). The International Rules in this book were formalized in the Convention on the International Regulations for Preventing Collisions at Sea, 1972, and became effective on July 15, 1977. The Rules (commonly called 72 COLREGS) are part...