Timber is a hugely capable civil engineering material, with the additional advantage of being sustainable. Trees, in particular conifers, make natural piles. Timber foundations may be particularly suitable for countryside structures such as bridges, forest chalets and activity centres, as well as post and beam timber buildings in waterfront or flood prone locations. This Digest gives information on the design and installation of timber piling, its history and background, suitable timber species and preservative treatment. 12 pages.