Pediatrics is the branch of medicine dealing with the diagnosis and treatment of internal diseases occurring in childhood. It a very broad discipline of medicine, which includes many specialties as subspecialties (ie. cardiology, pulmonology, gastroenterology, hepatology, etc.). Depending on the complexity of the health problem on which the patient complains, the pediatrician conducts diagnosis and treatment of the child in cooperation with other physicians specialized in a narrower filed of pediatrics. Similarly to the GP, patients visit the pediatrician’s office because of all kinds of diseases. Great progress in medicine and rapidly growing medical knowledge imposes specialization of physicians in more and more narrow areas of medicine. An experienced pediatrician skillfully employs the expertise of individual specialists still leading the overall treatment process of his or her patients.