How big a threat is state sponsored computer hacking?
In recent times, hacking has featured in the news a little more literally that organisations would like - everyone from the BBC to Reuters has had social media accounts compromised.
But governments themselves are believed to target other nations to search for intelligence, information and data that might be useful.
Dan Simmons visits a major cyber-security company to look behind the scenes at how - or if - inter-state hacking can be prevented.
The programme was first broadcast on Saturday 17 August 2013.