From the reviews:
"50th IMO - 50 Years of International Mathematical Olympia is a pleasant, entertaining, and informative volume. This lovely book 'is aimed at students in the IMO age group and seeks to demonstrate that mathematics is an active and lively subject, thousands of years old and yet young and fresh, as ever' ... . the book will be enjoyed by a wider audience. ... a beautiful book and a very interesting read for every one who is interested in mathematics and the IMOs - even if marginally." (Alex Bogomolny, The Mathematical Association of America, April, 2011)