AbstractSurgical interventions on infants with intersex characteristics are considered justified by some on the grounds that they carry a high risk of intolerable stigma. However, public understanding of intersex and its medicalization are under-researched. We review recent qualitative and quantitative studies of the understandings of intersex and its medicalization among people who have no particular professional or public experience of intersex. First, such laypeople reason about clinical dilemmas by drawing on values in similar ways as expert healthcare professionals do. Second, laypeople can over-estimate the utility of current ‘umbrella terms,’ including intersex, for people with direct familial experience of intersex. Third, beliefs about good and bad effects of medical intervention are affected by framing intersex as either a medical condition or the natural basis for a social identity. Fourth, sexual identity is the best evidenced predictor of opinions about early surgical intervention and its legal limitation on human rights grounds. We argue that possible stigmatizing reactions from the public may not be a solid basis on which to justify early surgical intervention on intersex characteristics.