Hillmer collaborates with other scholars on many of his book projects, often with the respected Canadian historian J. L. Granatstein.
In December 2016, Hillmer was named a Member of the Order of Canada.[1] He is a two time winner of the C.P. Stacey Prize for "for distinguished publications on the twentieth-century military experience."
O. D. Skelton: A Portrait of Canadian Ambition (Toronto: University of Toronto Press, 2015), xii, 424.
Canada's International Policies: Agendas, Alternatives, and Politics (Don Mills, Ontario: Oxford University Press, 2008) [with Brian W. Tomlin and Fen Osler Hampson], vi, 432 pp.
The Atlas of Canada and the World (Vancouver, Toronto, New York: Whitecap Books, 1999), 223 pp.
Prime Ministers: Ranking Canada's Leaders (Toronto: Harper Collins, 1999) [with J. L. Granatstein], 233 pp.
Elder Daughter of the Empire: A History of Canadian–British Relations, 1713–1982 (in Japanese; Tosui Shobo, Tokyo, 1997) [with Kazuo Kimura and P. A. Buckner], xii, 271 pp.
Empire to Umpire: Canada and the World to the 1990s (Toronto: Copp Clark Longman, 1994) [with J. L. Granatstein], ix, 373 pp. Revised and expanded as Empire to Umpire: Canada and the World into the Twenty-First Century (Toronto: Thomson Nelson, 2007), xiii, 393 pp.
For Better or for Worse: Canada and the United States to the 1990s (Toronto: Copp Clark Pitman, 1991) [with J. L. Granatstein], xvi, 334 pp. Revised and expanded as For Better or for Worse: Canada and the United States into the Twenty-First Century (Toronto: Thomson Nelson, 2007), xviii, 359 pp.
Negotiating Freer Trade: The United Kingdom, the United States, Canada, and the Trade Agreements of 1938 (Waterloo, Ontario: Wilfrid Laurier University Press, 1989) [with Ian M. Drummond], x, 197 pp.
O. D. Skelton: The Work of the World, 1923-1941 (Montreal and Kingston: McGill-Queen's University Press and The Champlain Society; both editions, 2013), xx, 53 page introduction, 517 pp.
Canadas of the Mind: The Making and Unmaking of Canadian Nationalisms in the Twentieth Century (Montreal and Kingston: McGill-Queen's University Press, 2007) [with Adam Chapnick], x, 326 pp.
Fuelling Progress: One Hundred Years of the Canadian Gas Association, 1907-2007 (Ottawa: Canadian Gas Association, 2007) [by Tim Krywulak], xi, 180 pp.
The Land Newly Found: Eyewitness Accounts of the Canadian Immigrant Experience (Toronto: Thomas Allen Publishers, 2006) [with J.L. Granatstein], 431 pp.
Canada Among Nations 2004: Setting Priorities Straight (Montreal and Kingston: McGill-Queen's University Press, 2005) [with David Carment and Fen Osler Hampson], x, 291 pp.
Battle Lines: Eyewitness Accounts from Canada's Military History (Toronto: Thomas Allen Publishers, 2004) [with J.L. Granatstein], 490 pp.
Among Nations 2003: Coping with the American Colossus (Don Mills, Ontario: Press, 2003) [with David Carment and Fen Osler Hampson], xii, 354 pp.
Activism and (Non)Alignment: The Relationship Between Foreign Policy and Security Doctrine (Stockholm: The Swedish Institute of International Affairs, 2002) [with Ann-Sofie Dahl], vii, 154 pp.
First Drafts: Eyewitness Accounts from Canada's Past (Toronto: Thomas Allen Publishers, 2002) [with J.L. Granatstein], 486 pp.
Canada Among Nations 2002: A Fading Power (Don Mills, Ontario: Oxford University Press, 2002) [with Maureen Appel Molot], xii, 299 pp.
Canada Among Nations 2001: The Axworthy Legacy (Don Mills, Ontario: Oxford University Press, 2001) [with Fen Osler Hampson and Maureen Appel Molot], xiv, 235 pp.
Pearson: the Unlikely Gladiator (Montreal and Kingston: McGill-Queen's University Press, 1999), x, 213 pp.
A Country of Limitations: Canada and the World in 1939/Un pays dans la gêne: le Canada et le monde en 1939 (Ottawa: Canadian Committee for the History of the Second World War/Comité canadien D'Histoire de la Deuxieme Guerre mondiale, 1996) [with Robert Bothwell, Roger Sarty, and Claude Beauregard], 295 pp.
Documents relatifs aux relations extérieures du Canada/Documents on Canadian External Relations, Volume XIII: 1947 (Ottawa: Affaires extérieures et Commerce extérieur Canada/External Affairs and International Trade Canada, 1993) [with Donald Page], xxxvii, 1654 pp.
Making a Difference? Canada's Foreign Policy in a Changing World Order (Toronto: Lester Publishing, 1992) [with John English], xx, 236 pp. French edition: La politique étrangere canadienne dans un ordre international en mutation: une volonté de se démarquer? (Québec: Centre Québécois des Relations internationales, Université Laval, 1992), 338 pp. Chinese edition. (Beijing: The Social Science Publishing House, 2002), 267 pp.
Partners Nevertheless: Canadian‑American Relations in the Twentieth Century (Toronto: Copp Clark Pitman, 1989), 322 pp.
Nearly Neighbours: Canada and the Soviet Union from Cold War to Détente and Beyond (Kingston: Frye Publishers, 1989) [with J. L. Black], xii, 174 pp.
On Guard for Thee: War, Ethnicity, and the Canadian State, 1939‑1945 (Ottawa: Canadian Committee for the History of the Second World War, 1988) [with B. Kordan and L. Luciuk], xx, 282 pp.
The Official History of the Royal Canadian Air Force, Volume II: The Creation of a National Air Force (Toronto: University of Toronto Press, 1986) [by W.A.B. Douglas], xix, 797 pp. Winner of the 1988 C. P. Stacey Award.
The First: Essays in Honour of Nicholas Mansergh (London: Frank Cass, 1980) [with P.G. Wigley], 192 pp.
A Foremost Nation: Canadian Foreign Policy and a Changing World (Toronto: McClelland and Stewart, 1977) [with Garth Stevenson], 296 pp.
The In‑Between Time: Canadian External Policy in the 1930s (Toronto: Copp Clark, 1974) [with Robert Bothwell], 224 pp.
