ERS | monograph Preface John R. Hurst It is a pleasure to introduce this edition of the ERS Monograph, focusing on pulmonary manifestations of systemic diseases. As clinicians, we strive to care for patients by carefully evaluating the available evidence, with reference to guidelines, and by relying on our own past experiences. However, when managing people affected by rare lung diseases, this process breaks down in three main ways. First, many of us will simply not have had significant personal experience of such conditions. Secondly, guidelines may not exist and, thirdly, the available evidence may be much more limited in scope and quality. This situation is true for many of the conditions discussed in the current edition of the Monograph, and I therefore have no doubt that the content will be incredibly helpful in managing some of the most difficult conditions in pulmonology. Indeed, I believe this Monograph will be important and of interest to specialists in other fields too, who are often the primary clinician for such patients. As respiratory clinicians and scientists, we are used to working in multi-professional teams. There is perhaps nowhere that this is more necessary than in managing the pulmonary manifestations of systemic diseases. The society is indebted to the Guest Editors for doing an excellent job in curating the individual chapters. I would also like to pay tribute to the chapter authors and peer reviewers who together have delivered a relentless focus on quality. Welcome to a new go-to reference work on Pulmonary Manifestations of Systemic Diseases! Disclosures: John R. Hurst reports receiving grants, personal fees and non-financial support from pharmaceutical companies that make medicines to treat respiratory disease. This includes reimbursement for educational activities and advisory work, and support to attend meetings. Copyright ©ERS 2019. Print ISBN: 978-1-84984-111-5. Online ISBN: 978-1-84984-112-2. Print ISSN: 2312-508X. Online ISSN: 2312-5098. https://doi.org/10.1183/2312508X.10033519 v