Dare, which already handles Sony Ericsson's digital advertising business, and Brando, its PR agency of record, will now take responsibility for devising a social media strategy for the telecoms giant, with a view to increasing its presence across networks such as Facebook, YouTube and Twitter.
The social media campaigns will also seek to engage blogging communities in an attempt to create a coherent voice online for Sony Ericsson UK & Ireland.
Dare picked up the Sony Ericsson digital advertising account in 2003.
Its most recent campaign, "hopper invasion", saw thousands of virtual space hoppers invade the Yahoo! UK homepage in conjunction with a Twitter campaign that allowed users to remotely pump up space hoppers by Tweeting the word "pumpt".