This isn't just a recreational book of puzzles - the aim according to author Lloyd King is to 'improve your ability to "think outside the box" and boost your creativity.'

It's an attractive concept that has some validity. Just as we need to exercise our physical muscles to achieve more with them, we need to give our mental muscles workouts at problem solving and idea generation, and one way to do this is through using puzzles.

Like King's previous book, Test Your Creative Thinking, this book is packed full of puzzles, 317 in all, ranging from the relatively trivial to the absolutely stumping. One or two are frustrating because the logic is a little twisted or depends on what something sounds like (risky if English isn't your first language), but there's certainly plenty here for a mental workout.

I'll be honest - this reviewer hates doing puzzles. Either I spot them straight away or can't be bothered with them, unless I really force myself. This makes them suboptimal exercises for me - but I still find it useful to do some occasionally alongside other mental stretching exercises (for instance developing metaphors, using more formal creativity techniques etc.) Probably the biggest single lesson is to look at each problem you are faced with in a range of different ways. Don't take things at face value. Watch out for the assumptions. It's easy enough to chant this mantra, but much harder to do it in practice - that's where plenty of exercise comes in.

As with Test Your Creative Thinking there is one health warning. Every real problem has many solutions, not just the one you can look up in the back of the book. (And, of course the real world doesn't have a convenient list of answers to look up the solution in.) 

All too often what you end up doing in solving puzzles not looking for a creative solution, but looking for the answer the author intended - the result is constrained thinking an analysis, not open thinking and creativity. This is a classic situation with cryptic crossword puzzles, where much of the trick is getting used to the puzzle setter's little ways - this indicates an anagram or whatever. Though the format is less constrained here, there are still certain ways of thinking that can be used to home in on the author's intentions.

However, once armed with this awareness, it's not a problem. Just make sure you try to come up with at least 2 solutions to each problem. Be as extreme, as wacky as you like. Bend the question or the answer. That way, when you check the answer in the back you can be smugly aware you did even better than the author! But that doesn't stop this book being highly recommended.