I take clinical material from a nine-month period in a slow open analytic psychotherapy group for mothers and babies, to illustrate its potential as a therapeutic modality. I describe the process of creating a reliable setting, or ‘group culture’, and its role as a prerequisite for therapeutic change. Vignettes are used, alongside my commentary, to display the passionate involvement between mothers and infants, also with therapists, which develops in a shared therapeutic experience. Relationships formed in this group provide the vehicle for its holding and containing capacity, as members grow up and live through, collapse and recover, re-visit and re-work their internal worlds through the group's weekly action.