Test your powers of logic with these challenging Su Doku puzzles.

A collection of 200 Difficult Su Doku puzzles of the highest quality from The Times newspaper. Perfect for the intermediate Su Doku solver in need of a constant supply of challenging puzzles, this book is guaranteed to provide hours of absorbing, brain-stretching entertainment.

Since the first Su Doku puzzle appeared in The Times in 2004, they have become a phenomenon, with over 5 million copies of The Times Su Doku books sold worldwide. You don't need to be a mathematical genius to solve these puzzles; it is simply a question of logic. Each puzzle has a unique solution – and there's no guesswork required.

The Times Su Doku remains the original, the best and the market leader.