Detailed designs for London Bridge station have been delivered by the HyderWSP joint venture to main contractor Costain.
Work is already underway on side to deliver the transformation as part of the £6 billion Thameslink Programme.
So far, three platforms have been demolished and associated track removed.
HyderWSP has now delivered more than 250 detailed architectural drawings to shape the stations redevelopment.
James Dessain, HyderWSP’s project director, said: “This is a major milestone for the JV and evidence of our effective working approach.
“The relationship between Hyder and WSP and the JV’s relationship with Costain is a real life example of the BS11000 being used in practice, and on one of the most complex station upgrades the UK has ever seen. Clear communication, high levels of productivity and efficiency, with minimal duplication have been crucial.”