The Wangduephodrang Dzong, a fortress-monastery built in the 17th century, is an outstanding example of traditional Bhutanese building tradition and is on the tentative list of world heritage sites. In a region of high seismicity, the 200 m long Dzong is located on a ridge between two rivers and is composed of three courtyards. The only free-standing building within the Dzong structure is the Utse, a 4-story tower made of traditional multi-leaved stone masonry walls with mud mortar and timber floors and roof structure. The Dzong burned to the ground in 2012. For its reconstruction the government decided to seize the opportunity to explore possibilities how to improve the earthquake resilience of traditional structures. While the clergy wanted larger and more sumptuous buildings, heritage conservation wanted an identical reconstruction, and the local engineering community suggested a reinforced concrete frame structure. After investigations, many iterations and a long consensus-finding process, a higher tower in traditional stone masonry with mud mortar but enhanced by concrete bond stones and special connections to modified timber floors, was built on a base isolated raft foundation. The paper focusses on the modifications of traditional building techniques to improve the seismic performance of heritage structures in Bhutan. Additionally, it is shown how a modern base isolation can be combined with a traditional tower with 1.8 m thick stone masonry walls. Apart from the technical interventions, the challenges of getting such interventions accepted by the stakeholders are highlighted.