In consultation with residents and businesses, the council plans to update the city's image and messaging with the aim of making it one of 'the most successful in the world' by 2020.
'A new brand will encourage inward investment, help us be competitive, encourage people to live and study here and make people proud of the city,' said Southampton head of communications Liz Kite.
The council has hired brand consultancy Placebrands, which is asking residents and local businesses to describe what Southampton means to them.
Questionnaires are being sent to 105,000 households and businesses via the council's civic newspaper.
A further 2,000 questionnaires will be delivered to traders and licensees.
Kite said a new brand identity would be in place by 2007.
The activity is part of the council's Southampton Community Strategy.