It's a fair bet that satellite navigation won't be at the top of the agenda when President Bush meets with European leaders in Ireland next week for the annual summit between the United States and the European Union. But, in the long run, a little-known agreement to allow New World and Old World satellites to play nice with each other could prove to be the summit item that has the greatest impact on average people worldwide.

For years, drivers have found their way home, and bombs have found their way to targets, because of the global positioning system, or GPS. The array of 27 American satellites gives receivers on the ground an accurate sense of where they are on the globe. Since the late '90s, Europeans have been working on their answer to GPS, called Galileo.

At first, the system was supposed to be a GPS competitor. But now, after years of wrangling, the United States and Europe have agreed to cooperate. That could mean more widely available tracking systems -- ones that work in just about every urban canyon, office park and hiking trail across the globe.

"Odds are, you'll get stronger reception, and more reliable services," said Ralph Braibanti, who directs the State Department's space and advanced technology office, and who negotiated the agreement for the U.S. side.

But it will take more diplomatic finagling to make the program work. Galileo's 30-satellite network is scheduled to come online in about 2008. Several people close to the project said they would be shocked if the deadline holds. Most of the financing for Galileo -- about 2.5 billion euros, or $3 billion -- is supposed to come from a public-private partnership. But European bureaucrats haven't yet settled on a private partner. And it's murky how that business will actually make money from the venture.

My Wired News article has details.