Stewart (pictured) has spent the last 20 years working in youth research in the Asia Pacific region after starting his career with MBL, which is now part of TNS.

From there he went on to have spells in the research departments at Coca-Cola China, Ogilvy and MTV. He then set up his own youth agency, Filter, which was sold in 2006. Most recently he was the Asia head of social networking site Friendster.

At TNS he will be responsible for building a specialist youth practice across the region and driving the TRU syndicated teen study throughout his territory.

James Fergusson, TNS’ global director for rapid growth and emerging markets said: “Ian’s appointment combined with TNS’ unparallelled footprint across the world’s growth markets and our strong digital offer places us in a unique position of being able to tap into youth [and] monitor its behaviour.”