This is the very first technical guideline on the European level for the fire safe use of timber structures and wood products in buildings. It aims at providing the highest scientific knowledge and covers the extended use of European design codes and standards, practical guidance, examples for fire safe design and principles of performance based design. The guideline presents information for architects, engineers, educators, regulatory authorities and building industry. The guideline is focusing on structural fire design by providing the latest detailed guidance on separating and load-bearing functions of timber structures under standard fire exposure. Reference is made to the Fire Part of Eurocode 5 and, where new knowledge is available, to other references. Depending on national regulations, some of the new design methods may need agreement by the competent authority. This new information will be potential input to the next revision of the Fire Part of Eurocode 5. The guideline also includes information on reaction to the fire performance of wood products according to the European classification system. The importance of proper detailing in building design is stressed by practical examples. Active measures of fire protection and quality of construction workmanship and inspection at building sites are presented as important means for fulfilling the fire safety objectives. The guideline has been developed within the European research project FireInTimber (Fire Resistance of Innovative Timber structures). Leading experts and researchers from nine European countries have been participating and guarantee its quality and relevance. The project has been initiated by the European initiative BWW Building With Wood under the umbrella of the European Wood Industries CEI Bois. It is sponsored by the European wood industry in cooperation with national funding organisations within the WoodWisdom-Net Research Programme.