Defending large-scale networks is exceptionally difficult to do in the face of one or many skilled adversaries with focused intent and time.

FORBES: Cyberwar Or Not Cyberwar? And Why That Is The Question

Agriculture Minister Michelle O'Neill said 2012 had been an "exceptionally difficult year" for farmers and the horsemeat controversy was "therefore a very unwelcome development".

BBC: Burgers recalled from NI schools are 'clear of horse DNA'

Even if you were inclined to do so, it is exceptionally difficult to get an accurate hold on which Twitter accounts are actually fake.

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Thanks to a highly regulated labour market and the enduring power of its trade unions, Sweden's rapidly growing numbers of immigrants have found it exceptionally difficult to get work.

ECONOMIST: Sweden's election

According to a source, the discussion was "exceptionally difficult".

BBC: SFO saved by cabinet revolt

There is remarkably little credible information regarding the quality of services that lawyers provide, and it is exceptionally difficult for even clients of lawyers to evaluate the strengths and weaknesses of their lawyers.

FORBES: Are Class Action Law Firms Too Corrupt to Go Global?

"This was an exceptionally difficult fisheries council, but with some stocks like North Sea cod on the verge of collapse urgent action has to be taken and large cuts were inevitable, " Mr Morley said.

BBC: News Online

At a victory celebration in the constituency, Mr Clegg said the party had won in the "most exceptionally difficult circumstances" - given the manner of Huhne's departure and allegations surrounding the party's former chief executive Lord Rennard.

BBC: Eastleigh by-election: Lib Dems hold on despite UKIP surge

This, many analysts believe, is going to be exceptionally difficult because almost all, not only U.S. allies, but almost all the countries around the word, particularly Arab neighbors, think at it is time for the sanctions regime to be lifted.

CNN: Christiane Amanpour: The British connection

Coping with exceptionally disruptive or dangerous prisoners is certainly an acutely difficult problem.

ECONOMIST: Prisons