Pulmonary thromboembolism in Japan is currently associated with a high mortality rate and remains a concern for patients and medical staff alike. Moreover, as the mechanisms of the condition have been elucidated, it has become clear that much work needs to be done in the field to achieve acceptable results in this country. Thus, Japan has regularly played host to the International Symposium on Pulmonary Thromboembolism . At the most recent symposium, in Sendai, the epidemiology and the treatment of pulmonary thromboembolism, traveler's thrombosis, and the prevention of deep vein thromboembolism were discussed, particularly with reference to the differences between Japan and Western countries. The fruits of the collaboration between that assembly of international specialists can be found in this collection of work. It provides an in-depth look at the current concepts that guide the treatment and prevention of the disease, and at the problem areas that must be improved upon.