Introduction A. Torres* and S. Ewig# *Servei de Pneumologia. Institut Clinic del Torax, ´ Hospital Clinic de Barcelona, Facultat de Medicina, IDIBAPS, Universitat de Barcelona, Centro de investigacion ´ Biomedica En Red-Enfermedades Respiratorias (CIBERES), Barcelona, Spain. # Thoraxzentrum Ruhrgebiet Kliniken fur Pneumologie und Infektiologie, Evangelisches Krankenhaus Herne und Augusta-Kranken-Anstalt Bochum, Bochum, Germany. Correspondence: S. Ewig, Thoraxzentrum Ruhrgebiet Kliniken fur Pneumologie und Infektiologie, Evangelisches Krankenhaus Herne und Augusta- Kranken-Anstalt Bochum, Bergstrasse 26, 44791 Bochum, Germany, Email: ewig@augusta-bochum.de N osocomial pneumonia, and particularly ventilator-associated pneumonia (VAP), is the second most frequent intra-hospital infection. The incidence of VAP has decreased in the last 5 years, from 14 to 9–10 cases per 1,000 days of mechanical ventilation. This has been an important achievement but nosocomial pneumonia and VAP still carry very high rates of morbidity and mortality and high financial costs. In this issue of the European Respiratory Monograph we have tried to attract new information in the field of nosocomial pneumonia and VAP and to appeal to physicians that directly or indirectly (microbiologists) manage this type of respiratory infection daily. Updates on the new advances in the aetiopathogenesis, epidemiology, diagnosis (including biomarkers) and treatment are provided by renowned authors. New treatment approaches and new antibiotics have also been reviewed and are presented by experts in the field. With regards to microbial aetiology, viruses and fungi are reviewed as potential causes of VAP by clinicians and are discussed in a chapter focussing on fungal VAP. Ventilator-associated tracheobronchitis, a highly controversial entity, is also discussed in one of the chapters. The chapters that deal with what we have learnt from animal models and subsequent preventive measures provide new and relevant information. Overall we believe that this Monograph is original as it includes new information, which has been published in the last 5 years. We want to thank all authors for their excellent contributions which, with without doubt, will help in the management of this important problem. Statement of interest S. Ewig has received fees for speaking and fees for research from Brahms (now Thermofisher). A. Torres has received speaking fees from Astellas, MSD and Pfizer, and research grants from Pfizer and Covidien. He is on the advisory boards of Astellas, MSD and Covidien. Eur Respir Mon 2011. 53, vii. Printed in UK – all rights reserved, Copyright ERS 2011. European Respiratory Monograph ISSN: 1025-448x. DOI: 10.1183/1025448x.10012611 vii