John Colville was one of those people who had the good fortune to be in the right place at the right time. The son of upper-class parents with good connections, he joined the Foreign Office soon after graduating from Cambridge University. At the start of the Second World War he began a diary to record his experiences of the conflict, not expecting that it would turn into a record of such momentous events. What made it into one was his secondment to 10 Downing Street as an assistant private secretary a little more than a month after the war began. From there he witnessed the fall of Neville Chamberlain, the ascent to the premiership of Winston Churchill, and Churchill's management of the war during their nation's "finest hour" and afterward, all of which he described within its pages. To his credit, when he edited it for publication four decades later he let his initial comments stand; though many of them proved inaccurate or embarrassing with the benefit of hindsight, they serve as a priceless measure of opinion at the moment they were made. Though Colville continued off and on in Churchill's service until 1955 and continued to record his impressions throughout his service, it is these early portions and his other vignettes of upper-class life during the war which make his diary such rewarding and enjoyable reading today.