The authors bring together the results of their three previous studies on wood decay. Theydiscuss the causes of decay, methods of examination/inspection of fungal infection, the physiology of wood-destroying fungi, and the effect of fungal decay on the physical properties of wood. The types of rots (i.e., fungi) found on standing coniferous trees, felled timber, and softwoods in use in buildings are listed. The occurrence and gross characteristics of the rot, microscopic details of the rot, physiological data, and economic importance of each fungus are presented. Prevention of decay during storage and shipment, and chemical preservatives are also discussed. -- AATA