The 'make.believe' tagline, devised by brand development agency 180, will be used to cover products and marketing from all Sony's businesses worldwide, including Sony Ericsson, Sony Pictures, Sony PlayStation and Sony Music.
The electronics company is looking to capitalise on convergence in its product areas. Sony plans to launch a 3D-compatible Bravia LCD TV in 2010, and is developing a web-enabled range of TVs.
In the coming months, both Sony and Sony Ericsson will employ the 'make.believe' brand positioning in high-profile marketing campaigns to mark their sponsorship of the FIFA World Cup.
Sony Ericsson's head of brand, Cathy Davies, said using the Sony umbrella branding would create 'more emotive brand activity'.
For the World Cup next year, the mobile handset manufacturer is launching a 'fan-centric' global campaign based on the theme of being the team's '12th man'.
Sony Ericsson is also using the tagline in its latest global campaign, created by Saatchi & Saatchi, Iris and Dare, for a trio of handsets, Yari, Aino and Satio.
The £8m UK ad campaign uses the line 'What if dreams could become reality?' and features people bouncing down the street on space hoppers. The ad ends with the words 'We're here to make it happen. Make.believe.'