The integration of the forest industry means the interlinkages between the pulp and paper industry on the one hand and the sawmill industry on the other hand. The reason for integration has to do with the characteristics of wood fibres. The best fibre for the pulp and paper industry is located in the outer parts of logs, while the sawmill industry can best use the inner parts. Therefore it makes sense to arrange both pulp and paper industry and sawmill industry in such a way that the sawmill waste, i.e., the outer parts, are sent for use in the pulp and paper mills as flexibly as possible. The profitability of the different sections of integrated forest industry is closely linked to one another.