Every four years the Racing Rules of Sailing are updated following the Olympics. To help the sailor, World Sailing labels important changes with marginal markings. For the new rules coming into force on 1st January 2025 there are quite a lot of marginal markings:- A third of the Definitions are marked, including Sail the Course, Mark-Room, Obstruction and Continuing Obstruction- Nearly a third of the rules in Part 2 (When Boats Meet) are marked, including Avoiding Contact, Mark-Room, Room to Pass an Obstruction- All of the rules in Part 5 (Protests, Redress, Hearings, Misconduct and Appeals) are markedThat's quite a lot of changes! You need a new set of rules and, to understand the implications of the changes, you need a guide to them.Rules in Practice has been the best-selling guide to the racing rules of sailing for the last 40 years. Now, in its 11th edition, it has been updated for (and contains in full) the 2025-2028 Racing Rules of Sailing.To begin, Rules in Practice describes the latest rule changes and their implications for sailors. The book then covers the fundamental rules that always apply to sailors along with a detailed look at the rules around luffing and keeping clear - which were an eye-opener to many sailors when they were first published in the last edition. As always, throughout the book, the emphasis is on the practical impact on you as a sailor, rather than a theoretical discussion of the rules themselves.This is brought to life in the rest of the book, which takes you around the racecourse, from start to finish, through the key situations that frequently occur showing, from the point of view of each boat in turn, what you may, must or must not do. (Other rules guides take you through the rules in order which is just not how you come across them on the racecourse.)You don't have to know all the rules off by heart, but you do need to know your rights and obligations on the water - the rules can be looked up afterwards. This knowledge will build your confidence while racing and enable you to make the most of opportunities when they arise.Colour diagrams throughout ensure concepts are easily understood. If you are going to buy one rule book - make it this one!