Starcom, which replaces Matters Media on the business, will begin work immediately on a brief for 2007.
In the year to June, Green & Black's spent £1.8m on media, according to Nielsen Media Research, and its investment is due to grow in line with the brand. It is the fastest-growing confectionery brand in its sector, having recorded 54% growth in value in the year to 15 July.
'As we look to expand internationally, the appointment of Starcom will provide access to a media network across key markets,' said Green & Black's marketing director Mark Palmer.