Certain issues surrounding the custody of children whose parents have separated (such as the question of shared custody when parents are in conflict and/or when children are infants or toddlers, the importance of the primary caregiver versus the child maintaining a connection with both parents and the relevance of inter-parent domestic violence and children’s views to custody and access arrangements) generate controversy at different levels – social, scientific, and judicial – because they challenge existing schools of thought or ideologies. Yet judges and custody experts have to make definitive rulings or decisions based on the best interests of the children whose custody is in dispute. The qualitative research we describe in this article was carried out in collaboration with 27 professionals: 11 judges from the Québec Superior Court and 16 social workers and psychologists with particular expertise around custody issues. The goal of our study was to examine the points of view expressed by those professionals on controversial child custody issues and analyse differences in the positions taken, on the basis of their social group membership (gender, professional category, and level of experience). The positions they adopted on the various issues were predicated primarily on the principle of continuity of access to both parents. A comparative analysis of the arguments invoked by respondents revealed no significant variations based on social group membership, apart from differences in the positions adopted by the judges and the custody experts on children’s need for stability and the weight that should be given in custody cases to preferences expressed by teenagers. The article concludes with consideration of ways these results might inform professional practice and avenues for future research.