SUMMARYIt is now generally accepted that there is a link between long haul air travel and venous thromboembolism. A similar risk is also recognised with other modes of transport including long coach and car journeys, and the term ‘traveller's thrombosis’ is to be encouraged instead of ‘economy class syndrome’. More research is required to quantify the precise risk, but the risk does appear to be small and largely confined to those with recognised risk factors, which include previous episode of thrombosis, hormonal therapy, recent surgery, malignancy and pregnancy. In addition, haematological abnormalities can predispose to thrombosis. Such thrombophilic disorders include the factor V Leiden mutation and deficiencies of natural anticoagulants such as antithrombin, protein C and protein S. General measures which can be taken to reduce the risk include leg exercises while seated. In addition, there is evidence to support the use of elasticated stockings, but evidence relating to the use of aspirin is less convincing.