This article outlines a conceptual framework for organising an intervention plan for family therapy before starting the sessions. This is based on an integrative coherent theory or frame of understanding called neuroaffective developmental psychology (NADP) (Hart 2008(Hart , 2011. NADP is an integration of attachment theory, neuropsychology, developmental psychology, and trauma theory. It has been developed as a tool to navigate in the complex world of emotional development, intersubjectivity, family therapy, and psychotherapy to create relevant intervention plans to meet the needs of an individual family or client. NADP is used as a theoretical frame of understanding, (a) to understand emotional development, personality vulnerabilities and disorders, and the maturation of emotional capacities within attachment-based relationships, and (b) to translate this understanding into intervention plans discretely adjusted to the complexity of human development and the skills and agency of the professionals working with the families. The theory and clinical application of NADP as an organising frame within a family therapy setting is illustrated by a case example.Keywords: emotional development, integrative personality theory, neuroaffective developmental psychology, neuroaffective triangle, attachment-based family therapy, intervention plan Key Points 1 Neuroaffective developmental psychology (NADP) is described as a conceptual framework for organising family therapy. 2 It promotes an understanding of emotional development, personality vulnerabilities and disorders, and the maturation of emotional capacities within attachment-based relationships. 3 NADP proposes a method to work out relevant intervention plans discretely adjusted to the complexity of human development and the skills and agency of professionals working with the families. 4 It facilitates neurological rewiring of deep emotional structures via transference and countertransference in the therapeutic relationship, utilising the neuroplasticity of the brain. 5 Structures in the brain dealing with emotions, empathy, sympathy, and mentalising need stimulation from synchronising with other human beings and psychotherapy may impact brain structures relevant for personality development.