Health and safety risks and environmental issues have lead to a series of restrictions in the use of traditional wood preservatives worldwide. As a result, novel chemical formulations are constantly being developed, as well as there is a resurgence of commercial interest in different non-biocidal approaches. This book aimed to identify the potential chemical (whether in use or in development stages), as well as non-biocidal approaches of wood preservation, appropriate to each of the European hazard class (EN-335-1), in the light of recent global restrictions on the use of traditional wood preservatives. The work starts with introduction and development of European hazard classes, followed by a brief section on the market and current use of preservatives in different hazard classes. Environmental and health threats associated with current solutions and restrictions on their uses are also mentioned separately.