The acronymn for Acceptance and Commitment Therapy, ACT, is said as one word: "act," because it focuses on how human behavior can change human suffering. The goal of ACT is to increase your psychological flexibility so that you can live (act) in alignment with your values. According to ACT, suffering comes from psychological inflexibility. Psychological inflexibility is a combination of avoidance of valued experiences, demanding control over things we cannot control, attachment to the content of our beliefs while losing sight of the context, and dissociating from the present moment.
I find that the principles of ACT can be useful for teens and young adults who are discovering their values and building their identity, sometimes for the first time outside their family of origin. These principles can also be useful for parents who are coming to terms with or redefining their parenting role.