A critical realist account is developed of two aspects of the study of power which are normally left implicit: the theory of causation presupposed and the way in which the normative connotations of power are dealt with. These matters are discussed partly by reference to Foucault’s views on power, particularly as set out in Volume 1 of The History of Sexuality. Regarding the conception of power as ubiquitous, it is argued this is not incompatible with concepts of causation or of power as deriving from the capacities of objects; indeed dispersed power presupposes causality and causal powers. Other concepts such as emergent powers, fields, structures and ecological dominance are also assessed from a critical realist standpoint. In the second part it is argued that the normative implications of power should not be evaded, and indeed that evaluation of the implications of power for flourishing and suffering are necessary for adequate description and explanation in social science. Positivist and Foucauldian refusals of normativity are critiqued by reference to the untenability of the fact-value and is-ought distinctions and the necessity of thick ethical concepts in social science. It is concluded that students of power should embrace causality and normativity.