When a timber building requires repairs, its frame must be put back to its original form using the same materials as the original construction. Difficulties arise because large trees are often not available and because conservation conventions are flaunted. The author discusses the French, British, Norwegian, and Japanese attitudes toward the conservation of timber buildings and summarizes the principles of building conservation set down at the 1983 ICOMOS Wood Committee Symposium. See also entries by the same author in ARCHITECTURAL CONSERVATION section.