Magnitude of the problem due to metabolic disorders is significantly high when these errors are considered collectively. In fact, they are best considered collectively because, though diverse, they have a common way of presentation. Moreover, most emergency management also is common to them with some differences. High index of suspicion is required for timely diagnosis and management. Best outcome is expected when a patient is diagnosed before symptoms appear. This understanding has lead to the idea of screening of all the newborns for inborn error of metabolism. Developed countries are using this approach universally. In India, it has not yet become a routine. Clinical features of most metabolic disorders mimic common illnesses (sepsis, birth asphyxia, etc.) specially in newborns. Diagnosis is suspected when baby does not respond to usual therapy and common conditions are ruled out. Initial diagnosis is mainly of metabolic disturbances like hyperammonemia, acidosis, hypoglycemia which need emergency management. Specific diagnosis needs special tests which are available only in specialized centers. Tandem mass spectroscopy (MS/MS) has emerged as a boon investigation for these disorders and needs only few drops of dried blood on a filter paper. With good transport and communication facilities now it is not very difficult to get these investigations done. Definitive management is specific for different conditions and may need introduction of special diets, the availability of those again may be a problem. In many conditions, specific treatment is yet not available. Financial constraints in developing countries often leads to problems for diagnosis and management.