John Lewis ad
Media playback is unsupported on your device

Will Sainsbury's and John Lewis TV ads pay back at the till?

Big retailers such as John Lewis and Sainsbury's have spent millions on their festive TV adverts.

But what makes a Christmas advert so successful? And do retailers make back what they spend?

Sarah Wood, the boss of Unruly, a marketing technology company, explains.

  • 19 Nov 2014