Prime ministers, the central figures in parliamentary government and the leaders of political parties, fill dominant roles in Canada’s political history. Their importance is recognized in the Dictionary of Canadian Biography/Dictionnaire biographique du Canada by the space devoted to them. Each political leader is presented by a notable Canadian scholar who, following the rigorous standards of research, writing, and critical judgement set by the DCB/DBC, has brought life and understanding to the careers of the individuals who have served in Canada’s pre-eminent political office. Canada’s Prime Ministers brings these well-written biographies together for the first time in order to provide readers with an opportunity to reflect on the striking variety of personalities who have succeeded in climbing the summit of Canada’s public life and the different challenges they faced in their determination to stay there. What insights into the workings of our public life do the biographies of these fifteen leaders provide? Did these very different men have anything in common that determined their success? The DCB/DBC biographies make it clear that although there is no standard mould that shapes Canadian prime ministers, prime ministerial success depends on both “character and circumstance.” The biographies suggest that one of the only commonalities between the prime ministers was an unstable mixture of personal ambition and a sense of obligation toward their country and their political party. Pragmatism in making policy and in devising strategies of survival, rather than principle or ideology, often seems the guiding determinant in the success of Canada’s federal political leaders. For a Canadian prime minister there is usually no higher ground than the claim to be the defender of national unity against threats of disruption and disintegration. In addition to these themes, the DCB/DBC’s fifteen biographies of Canada’s prime ministers is also an important historical reference tool, providing details about personal lives, sketches of close associates, a narrative of major events, and an assessment of accomplishments and failures set against the backdrop of economic and demographic growth, the social crisis of depressions, and the impact of world events. Together, they recreate the political and social panorama stretching from the campaign for confederation in 1867 to the struggle to entrench the Charter of Rights and Freedoms in the new Constitution of 1982. Told through the lives of Canada’s leading politicians this is a remarkable, engrossing, documented account of modern Canadian history.