Two years ago, Richard Moore, head of MI6, said that China was now the organisation’s ‘single greatest priority’.

Parliamentarians and the British public have been starkly reminded of this by last week’s news that a parliamentary researcher had been arrested on suspicion of spying for China.

This episode won’t be commenting on the ins and outs of that case, but talking more generally about Chinese espionage. What forms does it take, what are its goals and how successful are the Chinese secret services at achieving those?

Cindy Yu is joined by Nigel Inkster, the former director of operations and intelligence for MI6. He has served in Beijing and Hong Kong, and is now the senior adviser on cyber security and China at the think tank IISS.

Produced by Cindy Yu.