Although individual metabolic disorders are rare, collectively, inborn errors of metabolism are not uncommon and paediatricians should be alert to the possibility of such disorders. The presenting symptoms are frequently non-specific and may include lethargy, poor feeding, vomiting, coma, and seizures. After investigations, appropriate therapeutic options including exchange transfusion, peritoneal- and haemo-dialysis, forced diuresis, mega-dosing of vitamin cofactors, and special dietary therapy can be instituted, depending on the diagnosis. Somatic gene therapy may offer hope of a cure for inborn errors of metabolism in the future.