The board, created by Congress and appointed by Bush, focused on other classified work since it was named in spring 2005, but continued to press for a formal briefing by the National Security Agency.
A breakthrough was reached in recent days, and the five members were briefed by senior officials last week.
Board members said that they were impressed by the safeguards the government has built into the NSA's monitoring of phone calls and computer transmissions, and that they wished the administration could tell the public more about them to ease distrust.
"If the American public, especially civil libertarians like myself, could be more informed about how careful the government is to protect our privacy while still protecting us from attacks, we'd be more reassured," said Lanny Davis , a former Clinton White House lawyer who is the board's lone liberal Democrat.
Alan Raul, a former Reagan White House lawyer and the board's vice chairman, said he also was impressed.
"We found there was a great appreciation inside government, both at the political and career levels, for protections on privacy and civil liberties," said Raul, author of a book of civil liberties. "In fact, I think the public may have an underappreciation for the degree of seriousness the government is giving these protections."
