This paper describes the design and construction of a twelve storey office building which has base isolators (i.e. energy dissipators) and external cross bracing to resist lateral loads. The computer analysis techniques used are described and some comparisons are made with non-base isolated structures. The system shows a practical method of using base isolation and energy dissipation techniques in a multi-storey structure. The construction of the building has proved the system to be advantageous in terms of both cost and construction time.