The new building for the Triodos head office is situated on the estate De Reehorst, which is part of the National Ecological Network in The Netherlands. Therefor careful integration in the natural surroundings was a must. The office building (approx. 13,000 m2 GFA) has an organic shape and consists of three towers, that vary from three to six floors. At the ground floor and the lower stories, the towers are connected through a plinth building. The total supporting structure is designed in wood. Besides the basement and foundations, no concrete was used. The cores with oa stairs and the lift shaft, provide stability for the building. Thereby the building has become the first multistory office building with a timber core in The Netherlands and maybe in Europe as well. In addition of the timber core, the floors are supported by 26 Glulam columns. These columns are carefully shaped, smoothly converting into floor beams. This way in the façade maximum transparency is created to provide stunning views on the green outside. Floors and roofs are constructed from 120 mm thick CLT.