This chapter addresses conflicts of interest that might arise when there are ongoing custody disputes and, in particular, how legal instruments can be used where parents disagree regarding a decision concerning a child’s health. When a child is younger than 16 years, their parents must, as a rule, give consent regarding health matters. The child has a right, however, to be heard, and the parents ... [Show full abstract] must act in the best interests of the child. Through the analysis of several potential scenarios, the authors discuss, from a Norwegian legal context, whether parents in conflict are in fact able to act in the best interests of the child, and whether the child’s right to participation is respected. The authors conclude that the limited legal or other tools provided to parents and/or health institutions can lead to sole custody being the only way to resolve the disagreement. However, the authors also point out the dilemma in cases where the custody dispute or the parental conflict is the reason behind the child’s need for treatment.