Child development theory has come to be regarded as essential underpinning knowledge for social work practice, a view reinforced by the current research-minded agenda. Practitioners are enjoined to acquire a more in-depth knowledge of child development but in this paper it is argued that this agenda requires more scrutiny if social workers are going to engage more meaningfully with the child development literature and use it in a critical and reflexive way in their practice. To this end some key messages drawn from critical approaches to developmental psychology, a literature to date largely unrecognized by social work, are examined for their relevance to practice.