ERS | monograph Preface Robert Bals The use and prescription of antibiotics is an area of discussion, insecurities, a multitude of guidelines, a number of novel drugs and one of the most frequent medical interventions. The clinical spectrum of patients with infections of the respiratory tract is wide, and covers disease entities such as viral infections presenting as a common cold, “standard” CAP and pneumogenic sepsis with multiresistant microorganisms. While respiratory infections are among the most frequent diseases in pulmonary medicine, a number of problem areas are obvious: 1) there is often a lack of evidence-based approaches to therapy 2) the role of novel antibiotics is not well defined 3) the number of resistant microorganisms is increasing for a variety of reasons, from false application in patients to misuse in animal husbandry and 4) the inadequate use of anti-infectives can cause significant harm. With this ERS Monograph, we provide the reader with a broad and detailed overview on anti-infective drugs in pulmonary care. Several chapters focus on the pharmacology and clinical use of specific antibiotics or antifungals. Other chapters go into more detail on specific disease entities, such as asthma, COPD, pleural infections, TB and CAP. In addition, the book discusses current topics that cover subjects of broad importance, including resistance mechanisms, inhaled application of antibiotics, antibiotic stewardship, long-term treatment and novel drug developments. The Guest Editors, Stefano Aliberti, James D. Chalmers and Mathias W. Pletz, have worked very successfully to select these topics and to integrate these aspects into this ERS Monograph that summarises our current knowledge. I thank the Guest Editors and all of the authors for their excellent work. Together, they have produced a practice-guideline publication that comprises information on the scientific background and the application at the patient’s bedside. I am sure that this comprehensive overview will be useful for the clinical practice of Copyright ©ERS 2017. Print ISBN: 978-1-84984-083-5. Online ISBN: 978-1-84984-084-2. Print ISSN: 2312-508X. Online ISSN: 2312-5098. https://doi.org/10.1183/2312508X.10000817 v