Establishing and maintaining a sufficiently strong alliance with patients in group CBT can be challenging. It typically requires attention not only for monitoring the group process and the individual patient, but also for validating multiple patients. In the context of a 3-week intensive group cognitive therapy (IGCT), this chapter explores the conceptualization, development, and monitoring of therapeutic alliance, as well as how alliance ruptures can be prevented and managed in the treatment of adult patients in group settings. The chapter illustrates strategies of alliance-building and rupture repair in CBT groups, using clinical case and dialogue examples from group treatment of social anxiety disorder (SAD). In order to reverse processes that contribute to sustained symptoms, therapists will need to consider interventions that help to resolve tensions and maintain satisfactory alliance. Ruptures in alliance, e.g., when the patient does not engage, neglects homework assignments, misses sessions, or wants to terminate treatment, can then be detrimental to treatment progress. This chapter aims to integrate clinical experiences with research findings to provide CBT therapists with practical tools and advice. Case examples of alliance-building and alliance rupture repair linked to research findings are presented, demonstrating the overall significance of alliance for the outcome in CBT.