Much research has been done recently, and more is now in progress, to increase the effectiveness under tropical conditions of methods which have been developed in Europe for preserving timber. This book attempts to bring together the results of some of these studies. I have not attempted to cover the tropical zones of Central and South America as this would have extended the book beyond its limits. But I am grateful to the authors who have contributed chapters dealing with the different aspects and solutions of the problems of the tropical areas of the Old World. The International Research Group for Wood Preservation (The I.R.G.) at its annual meetings in different countries has provided a valuable forum for cooperation in this developing field. Anyone concerned with the subject would be well advised to study the publications issued by this group. Their office is at Drottning Kristinas vag 47C S - 11428 Stockholm, Sweden. Although timber is a renewable resource there is every reason why it should not be wasted through premature decay or the ravages of termites etc., when effective measures for its preservation are available and, if correctly applied, can greatly reduce the cost of maintaining timber structures.