Relationship-based infant mental health home visiting services for infants, toddlers, and their families intensify the connection between the personal and professional. To promote the therapeutic relationship and maximize the effectiveness of the intervention, home visitors must exercise good judgment, in the field and in the moment, to set and maintain appropriate, professional boundaries. The authors discuss the creation of professional boundaries, encouraging home visitors to apply "best practice" interventions on the basis of thoughtful evaluations of the setting and the nature of the family's needs.