There is relatively little Canadian military history which looks specifically at the questions and themes surrounding senior command (commanders of large formations of troops—normally generals or lieutenant–generals). Current interpretations call for a trilogy of abilities: the ability to defend national interests in the highest military (and often political) circles; the ability to organize and manage forces both before and during combat; and the ability to lead both directly and indirectly those who have to implement the plans. Were Canadians then, and are historians today, right to apply this multiple standard? This article looks at the three officers who commanded First Canadian Army during the Second World War: Generals A.G.L. McNaughton, H.D.G. Crerar and G.G. Simonds. Where these comanders might well possess one or two of these abilities they could as easily have little competence in the third. Overall Crerar comes out the best of the three.