After 27 years with headquarters at Av. da República, nº 42, in Lisbon, Teixeira Duarte needed to centralise the services that were already spread out in various premises and relocated its head office to the "Open" Building located at Av. das Forças Armadas, nº 125, also in Lisbon – ua building with better and more modern facilities and with an area that allowed the desired centralisation of teams and services.

The "Open" Building was built by Teixeira Duarte and was its headquarters until 2002, when it moved to the Lagoas Park development in Oeiras, also built by Teixeira Duarte.