The best age for funnel chest surgery, according to the latest and most authoritative ninth edition of the surgical textbook, is between three and five years old. Historically, there has been controversy over the best age for funnel chest surgery, with some pediatricians previously believing it should wait until adolescence. However, it has been found that by the age of five, children start to become more aware and might realize their chest shape differs from others, potentially leading to feelings of inferiority and reluctance to make friends. Thus, performing the surgery before the age of five—before the child is fully aware of their deformity—might actually be preferable, as it could minimize psychological and physiological impacts. Of course, there is also a viewpoint supporting surgery before the age of three, but the younger the child, the softer the chest bone, which sometimes allows for other potential corrective methods.