The relationship between parental affect tolerance and a distinct form of parent-child interaction that is located at the relational contact boundary, the limit, between the child and the adult is examined. Through the presentation of a parent therapy case of a 13-year-old girl, the paper suggests emotional self-awareness as a crucial mediator in one's ability to set limits consistently and parent effectively. Effective limit setting is highlighted as the critical parental task involved in seeing a child through the developmental phase that Winnicott referred to as the transition from object relating to object usage. Clinical approaches utilized to support this developmental process are presented with the aim of integrating theory and practice.