Marconi has picked Grey Advertising to handle its pounds 35 million corporate campaign promoting its transformation from a military supplier to a telecoms and information technology giant.
The agency network offices in London and New York will share the assignment, which is aimed at giving the UK-based company a clear positioning, particularly in the US market, and turn it into a more potent rival to Nortel, Cisco and Lucent.
Neither Steve Richards, Grey's managing director in London, nor Marconi would comment on the appointment. But industry sources say Grey has seen off a challenge from the Bates group to win the business.
The appointment reflects a major identity change for Marconi from its previous incarnation as the General Electric Company supplying armed forces.
Since then it has disposed of its defence electronics business to British Aerospace and pursued a voracious acquisition policy including the telecoms equipment business of Germany's Bosch as well as data communications specialists in the US.
Grey and Bates became the shortlisted finalists at the end of last year, surviving an original pitchlist which included D'Arcy and Young & Rubicam.
Marconi, which had previously worked with Athron Clark & Partners in New York, decided last autumn that it needed a global agency with integrated resources to differentiate itself from the competition.
About 45 per cent of the company's business comes from Europe, 30 per cent from the US and the rest from Asia. A through-the-line campaign is expected to break almost immediately to a wide-ranging customer base which includes BT and the US 'Babybells'.