The construction sector is responsible for a large amount of greenhouse gas emissions, energy and raw materials consumption and waste production. Thus, a shift towards sustainable construction methods is essential. Engineered timber, a leading material for sustainable construction, has advanced to a point where it can now be efficiently used for taller buildings. Unfortunately, designing taller buildings made from timber is more demanding compared to their concrete and steel counterparts. A successful design and construction of taller timber buildings requires intensive collaboration between different fields. COST Action HELEN aims to support the transformation from research on isolated topics to a more integrated, interdisciplinary approach. This shift is essential for the safe and economic design, construction, maintenance, and recycling of taller timber buildings.