For more than a half century, Arthur Schlesinger, Jr. was at the vital center of American political and cultural life. From his entrance into political leadership circles in the 1950s through his years in the Kennedy White House and up until his very last days, he was that rare thing, a master historian who enjoyed an extraordinary eyewitness vantage on history as it was being made. On intimate terms with many of the most prominent political, cultural and intellectual figures of the last fifty years, he was a man whose proximity to power never obscured his appreciation for the reality of those who have none. For that capacity for empathy and for much else, he was often called American liberalism's greatest voice. For most of his adult life, Arthur Schlesinger, Jr. dutifully recorded his experiences and opinions in journals that, until now, have never been seen. Edited by his oldest sons, they offer remarkably fresh and lucid observations on a half century of public life, and a rare and privileged view into the mind of one of America's most distinguished men of letters.