Couple conflict, which includes conflict over parenting practices, continues to be a topic of considerable interest to family therapists. Following parental separation, resolution or management of conflict over children has a special urgency. ‘High‐conflict’ cases present some of the most complex systemic and clinical challenges. In this first of two related articles in this issue of ANZJFT, we set out key ideas – some old, some new – about parental conflict from the divorce literature. We present Australian data on separated parents’ reports, which found significant conflict at three different points in time after separation and consider the clinical implications. We suggest that while ‘high conflict’ has an intuitive feel as a descriptor for difficult post‐separation disputes, it has limited utility as a blanket term to inform research and practice. The article acts as a conceptual backdrop to an earlier paper (Smyth & Moloney, 2017), in which we consider the dynamics of enduring ‘high conflict.’ We suggest that these cases might be qualitatively different to those cases in which intensely felt disputes develop but then recede. We also suggest that amongst enduring ‘high conflict’ cases there are likely to be cases with especially challenging dynamics such as interparental hatred.