The purpose of this discussion is to specify general conceptualizations of the power of an actor within a system of actors which bridge the gap separating the rigor and consistency of mathematical models of power from the realism and substance of empirical descriptions of power. Being powerful within a system of actors is defined metaphorically as the ability to convert resources into influence within the system. Three general aspects of this metaphorical definition are distinguished. The bases of power are converted into the manifestations of power via the processes of power. Static and comparative static properties of three formal conceptualizations of power based on the above metaphorical definition are specified and compared in terms of the quantitative, empirical description each provides of power among elite decision-makers in a small German community. Power as influence conceptualizes power in terms of its manifestations; structure in the influence relations among decision-makers. Power as control of valuable resources via possession conceptualizes power as an unobservable concept in which possession of resources as bases of power are inputs and the manifestations of power are outputs. Finally, power as control of valuable resources via possession and constraint conceptualizes power as an unobservable concept in which possession of resources and actor positions in the networks of economic/social exchange relations as bases and processes of power are inputs and the manifestations of power are outputs.