Empirical evidence continues to mount demonstrating the effectiveness of Acceptance and Commitment Therapy (ACT) across a wide range of conditions [1, 2, 3]. In many head-tohead trials, ACT outcomes are comparable to those in more established gold-standard treatments for a particular difficulty, but only sometimes outperform those treatments [4, 5*]. Thus, efforts need to shift from “Is ACT effective?” to researching processes of change that may provide guidance for how to further improve outcomes. One way to improve outcomes would be to focus on new transdiagnostic processes, such as self-criticism and shame, which have been shown to play important roles in a variety of psychological disorders and issues, including depression [6], post-traumatic stress disorder [7], borderline personality disorder [8], eating disorders [9**], schizophrenia [10], addiction [11**], paranoid ideation and social anxiety and [12] narcissistic personality disorder [13]. An important contributor to self-criticism and shame is the societal devaluation of stigmatized identities. Shame is the emotional core of the experience of stigma [11**] and tends to involve fusion with beliefs of being flawed or unlovable [14]. Self-stigma involves the internalization of a socially devalued status. Shame, the main emotional component of stigma, impedes social engagement [15], promotes interpersonal disconnection [16], and interferes with interpersonal problem solving [17]. The ashamed person’s perspective is narrow, focused inward toward thoughts of a “bad self” [۱۴]. In contrast to the socially-distancing and isolating effects of shame, compassion tends to evoke more flexible ways of responding and includes behavioral repertoires around caring for and relating to self and others that are associated with affilliative emotions such as warmth, interest, sympathetic joy, and pride [18]. As such, clinical interventions targeting shame and self-criticism often focus on fostering self-compassion [19, 20, 21].