FOR YEARS the West used a convenient formula for keeping the troublesome Balkan province of Kosovo on a back burner: "standards before status." By this the United States and European governments meant that Kosovo should develop stable democratic political institutions under a United Nations administration before any decision was made on whether it should become an independent state or remain part of Serbia, from which it was liberated by a 1999 NATO military campaign. The strategy proved to be a flop: The U.N. administration failed to rebuild Kosovo's economy or create a capable judiciary and government, while a NATO-led peacekeeping force flinched from preventing the creeping partition of the province into areas controlled by the Albanian-majority population and minority Serbs.

The Bush administration has consequently embraced a new tack, which is to deal with the hard question of Kosovo's status. With Washington's encouragement, the U.N. Security Council is soon to appoint an envoy to launch negotiations with Serb and Kosovar leaders. The idea is that, if the province's future can be settled, it will be easier for it to proceed with needed reforms and reconstruction. That may be true, but tackling Kosovo successfully will require a large investment of energy and resources by the United States and key European allies, both diplomatically and in Kosovo.

The Bush administration says it is prepared to make that commitment: Undersecretary of State R. Nicholas Burns paid a high-profile visit to Serbia and Kosovo last week to hammer home the message. The administration says it is open-minded about Kosovo's final status. But the best solution is readily apparent to most Western policymakers: Since returning Kosovo to Serbian rule is unacceptable to 90 percent of its population, it must become independent, probably under some form of international supervision. Serbia opposes this solution, but Western reasoning is that persuading its leadership to let go of Kosovo is a crucial step toward ridding Serbia of its poisonous nationalism and moving it toward integration with Europe's liberal democracies.

Making this policy work in practice will require overcoming the resistance not only of Serbian hard-line nationalists but of their backers in Russia. Even tougher will be overcoming the resistance of Kosovo Albanians to making reasonable concessions to the Serb minority -- such as allowing considerable autonomy in Serb-populated areas -- while stopping and reversing the Serb minority's attempt to break off northern parts of the province and annex them to Serbia.

The United States and the European Union will both have to take some of the very steps they've tried to avoid during the last several years. Most important of these is an E.U. commitment to a relatively rapid process of accepting Kosovo, Serbia and other states in the former Yugoslavia as members, provided they fully embrace democratic institutions and give up nationalist agendas. The Bush administration, for its part, will need to support integration of Serbia and other Balkan states into NATO and promise that U.S. troops will remain in the area for a few more years to ensure security. This is not an easy time for either the United States or Europe to take on such tasks. But as the experience of the last few years demonstrates, there will never be a good time to deal with Kosovo, and the longer a solution is delayed, the harder it may be.