I think anyone who wants to start doing some Olympiad level problems, this is the place to start. This book teaches mathematical arguments and how to solve tough problems. What I like about this book is it gives good examples before it gets to the problems. Solutions to all problems are in the back of the book. I deduct one star as I feel that some of the problems don't reflect what you've studied. I hate being dependent on solutions to answer questions. I will most likely buy Junior Section vol. 1, 2 and Senior Section vol. 1, 2. I don't know if I'd recommend other books in the series. I've skimmed through the first vol. of the series called "A First Step to Mathematical Olympiad Problems" and it tried to explain the problems and solutions with words, instead of showing the math step by step.