Aedas Architects has won planning permission for the highly controversial redevelopment of Birmingham's 1961 Chamber of Commerce building site.
The £80 million project has been given the all clear despite opposition from local community groups and the Twentieth Century Society, which was determined to save the existing John Madin building from demolition.
The development will incorporate 26,400m 2 of office space, a large proportion of which will be let, with the remainder used as the Chamber's new headquarters.
Local conservation campaigners have attacked the scheme, insisting that more of the original building should be preserved.
However, Aedas said it was working to preserve a John Piper mural, one of the most important historical elements of the site.
Work is due to start on site in late 2005 and completion is expected by 2007.