In this article, we describe the nature of therapeutic collaboration between psychotherapist and group participants in mindfulness-based cognitive therapy (MBCT), which occurs in a group format and incorporates cognitive therapy and mindfulness practices with the aim of preventing depression relapse. Collaboration is a central part of two components of MBCT: inquiry and leading mindfulness practices. During the process of inquiry, the therapist-initiated questions about the participant's moment-to-moment experience of the practice occurs in a context of curious, open, and warm attitudes. In addition, collaboration is maintained through co-participation in mindfulness practices. We provide a case illustration of collaboration in these contexts and conclude with recommendations for clinical practice.