During the course of the twentieth century, nineteen men and one woman--from the Third Marquis of Salisbury to Tony Blair--have occupied the post of Prime Minister of the United Kingdom. In a series of biographical essays, Dick Leonard, a leading political journalist and former MP, recounts the circumstances that took them to the top of "the greasy pole", probes their personal and political strengths and weaknesses, assesses their performance in the top office and asks what lasting influence they have had.