Bounded rationality, opportunism, the primacy of markets and the action of economizing are building blocks of Oliver Williamson's Transaction Cost Economics (TCE). As in all intellectual exchanges, Williamson has used a range of argumentative devices to set up and negotiate his basic notions and assumptions with economists. Rhetorical analysis is applied here to study his argumentation in a certain institutional context within economics. Negotiations with the mainstream, with the competence view of the firm and within the New Institutional Economics, for instance, have had an impact on the construction of TCE and are given attention here. Difficult decisions have been made in order to forge ahead with TCE, including whether to uphold some notions (e.g. opportunism) at the cost of leaving others behind (e.g. economics of atmosphere). Rhetorical transactions like this have shaped TCE and its recognition in economics and related areas.