Birmingham New Street is the busiest UK rail station outside of London. Growing demand following upgrade works to the West Coast Main Line has seen passenger numbers exceed the design capacity of the current station, which was constructed in 1967. To meet projected increases in passenger numbers, a redevelopment of the historic station is currently underway. Retaining all major structural features, the redevelopment is being undertaken over a live railway in the heart of Birmingham while maintaining existing passenger capacity.This paper describes the structural assessment and strengthening design work undertaken to facilitate the regeneration of Birmingham New Street. The assessment methodologies used in examining this historic concrete structure are discussed before the design of subsequent strengthening works is presented.