Preface Since the beginning of the last century, respiratory medicine has evolved as a specialism from the study of respiratory physiology. Consequently, for over a hundred years, obstructive airway diseases such as asthma and chronic obstructive pulmonary disease have been an important focus of chest physicians. Although these diseases are still of continued importance, the spectrum of pulmonary diseases now studied has been greatly expanded and includes thoracic oncology, allergology, pulmonary infections, sleep medicine and intensive care medicine. In addition, the collaborations between paediatricians and pulmonologists and between surgeons and pneumologists have become more and more important. In the preface to the previous issue of the European Respiratory Monograph (ERM), whose topic was bronchial infections, I pointed out that the 21st century will one day be described as the century of infectious diseases. The economic crisis has contributed to a deterioration of the social and hygiene conditions in many parts of the world, creating a breeding ground for the spread of infectious diseases. Antibiotic overconsumption has led to an exponential growth of resistant organisms. The globalisation of the economy has contributed to the spread of these resistant infectious agents, while the development of new antibiotics has not kept pace with the development of resistance. Therefore, surgical measures again play an essential role in the treatment of infectious pathogens, as was the case in the era of tuberculosis before World War II. The present issue of the ERM summarises the most important infectious diseases that need a common therapeutic approach between thoracic surgeons and pneumologists. I want to congratulate the Guest Editors, Gernot Rohde and Dragan Subotic, for their tremendous work in setting up this excellent trendsetting ERM, which should be of interest to pneumologists, infectious disease specialists and thoracic surgeons alike. I hope this book will stimulate joint research, leading to better understanding and more successful therapy, and I am convinced that readers will find this ERM useful for their daily work. Eur Respir Monogr 2013 61: v. Copyright ERS 2013. DOI: 10.1183/1025448x.10007713. Print ISBN: 978-1-84984-036-1. Online ISBN: 978-1-84984-037-8. Print ISSN: 1025-448x. Online ISSN: 2075-6674. v