The revised International Health Regulations, adopted in 2005, provide a legal framework for a more effective coordinated international response to emergencies caused by outbreaks of infectious diseases. A number of provisions are relevant to the detection and control of TB during air travel, strengthening the authority of WHO and of national public health authorities in this domain. Because of these important developments since the original guidelines were issued in 1998, WHO has prepared this revised version to take account of current public health risks that may arise during air travel and new approaches to international collaboration in dealing with them.