The rapid dissemination of innovation through the economy via spill-over effects has a hugely positive impact on economic growth, he says.

ECONOMIST: Economics focus

Worsening shortages of food and medicine in both eastern and western Libya mean that a conflict prolonged and intensified by outside intervention could create a nationwide humanitarian disaster, whose effects will spill over into those countries that may have the best chance of a successful political transition to more representative government.

FORBES: Gary Johnson to Obama: 'Time's Up in Libya'

The effects of the euro crisis will spill over from developed to emerging economies, the ILO says, pushing youth unemployment to almost 13% by 2017.

BBC: Youth unemployment 'set to rise'