I think that there could be many different ways to read Foucault's notion of power in both of Williams' work. In the case of Blanche, Stanley uses the notion of insanity and mental illness to exert power over her and to control Stella. While Blanche might be suffering from some level of mental illness, Stanley uses this label as a construct of power in order to maintain his control over Stella and not disrupt the distribution of resources that are in accordance with the trappings of power. In this case, the determination of mental illness, the exclusionary practice to consolidate the control of those who have power over those who lack it is evident in the rushed manner in which Stanley convinces Stella to commit her sister. In much the same manner, Amanda is able to exert her control over the family, Laura in particular, because she creates the persona of her daughter being challenged or mentally incapacitated. While Amanda would never admit it because of the social stigma or shame it would cause, part of her ability to extol the virtues of her own youth and create a sense of nostalgia her own past is because Laura is so very different. In this setting, the construct of power and control is only evident when the term "mental illness" or "different" is applied to Laura, whereby she is seen as inferior and insufficient while Amanda is supposed to represent the accepted and "good" norm.