Hunting large groups and then capturing them is one of the great joys of the game of Go. It is the privilege of every amateur who plays Go for pleasure to develop their own style of attacking. There are numerous examples of players who, with great zeal and energy, attack and hunt small worthless groups, only to suddenly realize that their opponent has enclosed them with a thick wall or that their elaborate attacks have missed the target, ultimately securing insufficient territory. In the current boom of Go books, there are many books on Joseki and Tesuji, but surprisingly few that explain the fundamental principles of proper attacking. This is an unacceptable situation for players who want to learn how to attack correctly. Therefore, says Kato Masao, he has written this book.