Child protection reform has been difficult, despite evidence that practice should be more child-centred, respectful and responsively inclusive of family and communities. An Australian survey of 387 third parties working with statutory child protection authorities revealed widespread support for reform, but significant opposition to child protection authorities. Only police aligned themselves with child protection authorities. Welfare and family workers were most likely to have defiant postures of resistance and disengagement and to criticize child protection authorities for their bureaucratic ritualism, poor accountability, low trustworthiness and social exclusion. Lawyers and special service providers shared some of these criticisms, while health and educational professionals remained neutral. System reform is likely to grind to a halt when essential third parties are adopting oppositional positions. Principle-led communities of practice that are multidisciplinary and community-inclusive may offer the best hope for cutting through reform gridlock and broadening and deepening capabilities.