later in the Monograph, we have included a chapter around the ethics of neonatal resuscitation, which is a crucial topic to ensure our clinical actions are in the best interests of babies [11]. Of course, not all lung disease in the neonatal period relates to prematurity. In the next section of the Monograph, the chapters describe disorders of all aspects of the respiratory system in the neonatal period, including infections [12], and congenital and acquired problems affecting central drive, the large airways, lung parenchyma, the lymphatic system [13], the interstitium, and the diaphragm [14]. These are rare but significant diseases, which carry substantial morbidity and mortality, and necessitate close working between neonatologists and paediatricians. We have also included a chapter on CF in the neonatal period which, in keeping with this Monograph, describes a condition that is worlds apart from the condition we saw 20 years ago, and in which the goal is to get the early years right in order to enable a long and healthy life [15]. The chapters discussing radiological [16] and histological [17] investigations are included because these tests are so crucial to making the right diagnosis and helping guide treatment. We finish with a broader view of some of the wider considerations around neonatal lung disease. Socioeconomic determinants of health in the neonatal period are an area in which we are developing a greater understanding, and this is a timely chapter given that health inequalities have been brought so sharply into focus during the coronavirus disease 2019 (COVID-19) pandemic [18]. We are also conscious of the fact that much discussion around health and neonatal care focusses on high-income settings, so we are delighted to share some insights into these problems in low- and middle-income countries [19]. The burden of preterm birth is no less profound here, and it is heartening to see collaborations and networks forming to help develop effective and cost-effective approaches in low- and middle-income countries. We extend our immense thanks to the authors of these chapters, who we feel have done a stellar job. The authorship includes world-leading authorities, and up-and-coming stars in the field. We have convened a mixture of healthcare professionals and scientists, from around the world, and this has brought a diversity to the Monograph that is appropriate, given the global nature of the problems of neonatal lungs. We are grateful to the all the expert reviewers who gave up so much of their time to help us. The Monograph was compiled during the COVID-19 pandemic, and the efforts that our authors and reviewers have made during these challenging times is hugely appreciated. We are also very indebted to the excellent team at the ERS Monograph, comprising John R. Hurst (Editor in Chief), Rachel Gozzard (ERS Monograph Managing Editor) and Caroline Ashford-Bentley (ERS Editorial and Library Services Coordinator). Their enthusiasm and experience has kept this project on track, and their desire to develop a Monograph for babies has been inspiring. We have really enjoyed commissioning, reading, reviewing and editing the chapters, and we sincerely hope you find them as useful and interesting as we did. References 1. Swarr DT, Deshmukh H, Zacharias W. In utero and post-natal development of the human lung and its defence mechanisms. In: Sinha IP, Bhatt JM, Cleator A, et al., eds. Respiratory Diseases of the Newborn Infant (ERS Monograph). Sheffield, European Respiratory Society, 2021 pp. 1–20. 2. LoMauro A, Zannin E. Respiratory physiology. In: Sinha IP, Bhatt JM, Cleator A, et al., eds. Respiratory Diseases of the Newborn Infant (ERS Monograph). Sheffield, European Respiratory Society, 2021 pp. 21–37. x https://doi.org/10.1183/2312508X.10006621