An interesting side remark in an article by Declan Walsh that was published in Thursday's NYT:

“The danger that American intelligence work can taint an entire profession has been the subject of debate and restrictions since the 1970s. By policy, the C.I.A. has not placed spies abroad under cover as Peace Corps volunteers or American Fulbright scholars. They cannot pose as journalists accredited to American news organizations except with a waiver from the president or the C.I.A. director.”

(Read the complete article here.)

In other words, American spies can pose as journalists accredited to German, Dutch or Canadian news organizations, without a waiver from the C.I.A director or president.