"We have to find a way to not only have better control over who we receive e-mail from, but also to authenticate or trace the e-mail, " says an executive for a major brokerage firm, who asked not to be named.
And a member of his staff supervised that personally to make sure that that happened, leaving no possible trace of e-mail evidence or other what - other things that he left behind.
These include closer co-operation between national intelligence agencies, the creation of an EU counter-terrorism chief, and measures that make it easier to trace terrorists who use mobile phones and e-mail.