In Sickness and In Power looks at illness in heads of government, business and military leaders between 1901 and 2007. It considers how illness and therapy - both physical and mental - affect the decision-making of heads of government, engendering folly, in the sense of foolishness, stupidity or rashness. Owen is particularly interested in leaders who were not ill in the conventional sense, whose cognitive faculties functioned well, but who developed a 'hubristic syndrome' that powerfully affected their performance and their actions. As we learn here, they suffer a loss of capacity and become excessively self-confident and contemptuous of advice that runs counter to what they believe, or sometimes of any advice at all. Long fascinated with the inter-relationship between politics and medicine, David Owen uses his deep knowledge of both to look at sickness in political leaders. Owen expertly scrutinises such diverse political personalities as Sir Anthony Eden at the time of Suez in 1956; John F. Kennedy and the Bay of Pigs fiasco in 1961; the last Shah of Iran; and President Mitterrand of France who suffered from prostate cancer. The author also devotes a chapter to the hubristic behaviour and relationship between President Bush and Prime Minister Blair. The book ends by outlining some of the safeguards that society needs to address as a consequence of illness in heads of government. Revised and Updated Edition for 2016 including a new chapter entitled Hubris Syndrome in the Military.