Most of us are guilty of putting items in our shopping trolleys without giving one moment's thought as to where they came from. Jo McFarland doesn't have that luxury, because she's the one in charge of sourcing thousands of items - from around 500 factories in China - for two of the most famous high-street retail names in the United Kingdom, Sainsbury's and Argos.

Sourcing manufactured goods may sound a little prosaic, but Jo's story brings the world of factories in China directly to our doorstep. And it's a world that has defined China's integral position in the global retail supply chain for the last two decades.