Most United Nations agencies rely for family tracing on the International Committee of the Red Cross, the global network of national Red Cross and Red Crescent societies. Florence Anselmo, who directs the I.C.R.C.’s Central Tracing Agency, said that the I.C.R.C. and United Nations agencies can’t look in one another’s databases. That’s necessary for privacy reasons, but it’s an obstacle to family tracing.

Another problem: Online databases allow the displaced to do their own searches. But the I.C.R.C. has these for only a few emergency situations. Anselmo said that most tracing is done by the staff of national Red Cross societies, who respond to requests from other countries. But there is no global database, so people looking for loved ones must guess which countries to search.

The organization is working on developing an algorithm for matching, but for now, the search engines are human. “When we talk about tracing, it’s not only about data matching,” Anselmo said. “There’s a whole part about accompanying families: the human aspect, professionals as well as volunteers who are able to look for people — even go house to house if needed.”

This is the mom-and-pop general store model of tracing: The customer makes a request at the counter, then a shopkeeper with knowledge of her goods and a kind smile goes to the back and brings it out, throwing in a lollipop. But the world has 65 million forcibly displaced people, a record number. Personalized help to choose from limited stock is appropriate in many cases. But it cannot possibly be enough.

Refunite seeks to become the eBay of family tracing. In 2005, Christopher and David Mikkelsen helped a friend, an Afghani refugee in Copenhagen named Mansour, look for his family. The Mikkelsens eventually found one of his brothers in southern Russia, and helped Mansour and the brother to meet. “The agency in Denmark literally did not know what its counterparts in Sweden or Australia had,” said Christopher. “This was absurd.”

Christopher was a musician and writer, and David was a documentary filmmaker. “We didn’t know anything about refugees, or about technology,” he said. “But we thought: People scatter globally. We need a global solution. Just create a simple Excel spreadsheet and share it internationally! How hard can this be?”

Pretty hard, apparently. During 2006 and 2007, the brothers took their idea to international agencies and refugee aid groups all over the world. No one bit.