The book discusses new concepts and findings in the field of pulmonary function. This function is notably associated with spirometry and gas exchange at the lungs. The technique of spirometry, its clinical meaning, and reference values have all been refined over decades of its use. Although spirometry remains ancillary in diagnosis-making, it seems hardly replaceable in monitoring of lung disease progression and treatment efficacy. Pulmonary function goes far beyond spirometry. It encompasses interactions with the cardiovascular system, sleep disordered breathing, etiological factors like occupational bio aerosol exposure or cigarette smoke related issues. Pulmonary function may crumple in any respiratory ailment, the case in point being all too often respiratory tract infections. Chapters contribute to the latest thinking on molecular mechanisms underpinning pulmonary function, on patient care and attempt to keep up-to-date with current clinical and research progress. The book will be of interest to both clinicians and biomedical researchers.