Sudoku and its variants have become an increasing form of entertainment in recent years for a large number of people. They can of course be solved by brute force trial-and-error methods, but with the strategy described here, such methods are rarely needed. This book is a step-by-step guide to that strategy, described in 15 Chapters with almost 200 individual diagrams. Part 1 is devoted to Sudoku itself, and in 8 Chapters it describes the solution method, increasing in complexity from solving the very simple elements and progressing to elements which are linked 5 or more along a row, column or 3x3 square. Part 2 describes Sudoku related puzzles such as Samurai Sudoku and I-doku. Later, the book describes Kakuro and the challenging Killer Sudoku, again providing step-by-step instructions. In Chapter 14, some mathematical background is given and a Sudoku with the minimum number of clues is presented along with its solution.