In 1947 the Dutch forensic pioneer Co van Ledden Hulsebosch published his memoirs entitled ‘Veertig Jaren Speurderswerk’ (Forty years of Detective Work). In an engaging and humorous manner Co discusses the many cases that he investigated and solved using criminalistic reasoning and forensic science methods. The book was very popular at the time and needed to be re-printed 4 times (in total 5 editions appeared).