This book represents a comprehensive review of the most recent developments in paediatric pulmonary function testing and their clinical applications in common paediatric respiratory disorders. The first section reviews the current lung function tests used in infants and toddlers who are by nature unable to cooperate with most testing procedures. It describes the methodologies, provides normal values where available, and gives advice for data interpretation. The second section deals with the classic adult-type pulmonary function tests and their application in the semi-cooperative or cooperative older child. Age-related technical issues and the limitations of these tests are considered. Tests assessing the respiratory system beyond the usual measurements of mechanics, lung volume, and bronchial responsiveness are covered in the third section. These include the measurements of respiratory muscle function, work of breathing, diffusing capacity, and inflammatory markers in exhaled air and breath condensate. The fourth section discusses the clinical usefulness of pulmonary function tests in the diagnosis and management of the most common paediatric respiratory disorders including asthma, cystic fibrosis and neuromuscular disorders, as well as in the follow-up care after lung or bone marrow transplantation or after neonatal lung disease. This part is unique, since no books previously published in the field of paediatric lung function testing have considered its clinical value in the individual patient. Finally, the future role of pulmonary function testing in the neonatal and paediatric intensive care unit is evaluated. Practical and up-to-date, this textbook is of special interest for paediatric and adult pulmonologists, paediatric intensivists, general paediatricians and physicians in training for these specialties, as well as for pulmonary function technicians and respiratory therapists