When Mr. Nicolaides told me he was editing a book on Thromboem­ bolism I was constrained to say "not another" for there have been a number of recent contributions to this field. Yet venous thromboembolism is a major accompaniment of nearly all forms of medical and surgical illness. All clinicians should know about it; all should be able to integrate their knowledge into clinical management. The problems remain of what to know and where to find it, particularly in a field which draws increasingly on other areas for its fundamentals and which is also changing fast. This volume is a brave endeavour to provide a view over the whole subject. It could not possibly succeed absolutely and both editor and contributors undoubtedly realise this. Nevertheless they have put at our disposal know­ ledge of a wider kind than that available before and thus made it possible for the relatively inexpert such as myself to perceive how complex are the disturbances we produce by surgery or are produced by illness and where we can hope for advances in understanding and therapy in the future. A text of this kind hardly needs a foreword-it is of self evident value, although I expect the pace set by its writers and others in the field will, with the additional stimulus provided by this synthesis of ideas that has been achieved, soon require another volume. In the meantime it is a timely venture. H. A. F.