Introduction Christoph Lange*,#," and Giovanni Battista Migliori+ *Division of Clinical Infectious Diseases, # Medical Clinic, Research Center Borstel, Borstel, " Center for Infection and Inflammation, University of Lubeck,¨ Lubeck, ¨ Germany. + WHO Collaborating Centre for TB and Lung Diseases, Fondazione S. Maugeri, Care and Research Institute, Tradate, Italy Correspondence: C. Lange, Clinical Infectious Diseases, Research Center Borstel, Parkallee 35, 23845 Borstel, Germany. E-mail: clange@fz-borstel.de Although the global incidence of tuberculosis (TB) is slowly declining, the disease still remains one of the leading causes of morbidity and mortality worldwide. In many regions of the world, including parts of Europe, the high incidence of TB is an indicator of poverty and healthcare inequalities. In countries with a low incidence of TB, the disease is mainly related to risk group for example, recent close contacts of infected index patients, migrants from high-incidence countries, HIV-infected individuals, and those with other immunodeficiencies and co-morbidities. Targeting these groups in order to prevent TB is particularly important if the ultimate goal of eliminating the disease is to be achieved. The emergence of antimicrobial drug resistance in Mycobacterium tuberculosis strains with multidrug- (MDR) and extensively drug-resistant (XDR) profiles has become a major obstacle to achievement of the Millennium Development Goal of TB, which aims for the elimination of the disease by 2050. However, for the first time in many centuries, new drugs for the treatment of TB will soon become available. These new weapons must be used wisely. There may be a further barrier to disease elimination: medical students and even residents of internal medicine from industrialised countries may complete their education without seeing a single patient with TB. This lack of experience is reflected in the diagnostic delay seen in these countries. However, important advances have been achieved in the prevention, diagnosis and treatment of TB in recent years. This has been due to the hard work and dedication of leaders in the field, many of whom have kindly agreed to contribute to this issue of the European Respiratory Monograph (ERM). We are very grateful for their commitment to the field and for their support in the compilation of this publication. This issue of the ERM includes up-to-date information on TB epidemiology, as well as control and elimination strategies. TB prevention, including the latest developments in novel vaccine research, and recent advances in the diagnosis and treatment of latent infection with M. tuberculosis, are also presented. The issue also covers state-of-the-art diagnosis of TB and the treatment of active TB in patients from different risk groups, including cases of M. tuberculosis drug resistance and complications of therapy. We hope that this issue of the ERM will prove a useful and valuable reference source to our colleagues, and will inspire young clinicians and scientists to enter this fascinating field. Eur Respir Monogr 2012 58: viii. Printed in UK – all rights reserved, Copyright ERS 2012. European Respiratory Monograph DOI: 10.1183/1025448x.10039512. Print ISBN: 978-1-84984-027-9. Online ISBN: 978-1-84984-028-6. Print ISSN: 1025-448x. Online ISSN: 2075-6674. viii