At the core of this thesis is an attempt to address two primary questions: is Canada a middle power and how can we tell? As such, there are a variety of corollary questions: What is a middle power? What characteristics do middle powers have? And finally, is a state's middle power classification sourced in behavioural or capability characteristics? All of these questions are addressed here, and ultimately it is concluded that Canada is and was a middle power on the basis of the selected behavioural and capability indicators, and that both behaviour and capability are useful elements in differentiating or predicting whether a state is a middle, small, or great power.