The agency has been brought in on a project basis to help launch its HSBC Emerging Market Index - a forward-looking index that launched this week charting the development of emerging markets around the world.
HSBC head of media relations Richard Lindsay said: 'It is the most international campaign HSBC has ever launched. The index is an ongoing project and we will work with Weber Shandwick at least into 2010.'
The work is being managed from the agency's London and Hong Kong offices, with a focus on Asian markets.
WS won the account via a competitive pitch that came out of the aborted tender for HSBC's unified global PR account earlier this year.