"Undiscussables" are topics associated with threat or embarrassment that are avoided by groups, where that avoidance is also not discussed. Their deleterious effect on executive groups has been a point of discussion for several decades. More recently critical action learning (AL) has brought a welcome focus to power relations within AL sets. This paper brings these two streams of research together by exploring the relationship between undiscussables and the exercise of power by AL leaders. Analysis of statements and actions at times of negative affect in various AL sets over a two-year period showed three distinct categories of activities of AL set leaders that seemed effective in generating undiscussables within the set. It is argued that each of these categories represented an exercise of power by AL set leaders as they accessed privilege associated with their rank. Also proposed is that these activities seemed to be done without awareness by the AL set leader, with that lack of awareness being central to achieving the result of undiscussables. The paper concludes by inviting both AL set leaders and members to consider the described activities as a means of growing awareness about their role in generating undiscussables.