It has been a good week for NATO. There was more common ground than disagreement at meetings between member foreign ministers in Budapest and at the five-day NATO Parliamentary Assembly, which convened in Vilnius, Lithuania. There were even tangible accomplishments on such thorny subjects as Turkey and Macedonia. Those successes will also serve as confidence builders as NATO tackles difficult topics such as expansion and missile defense, issues that are sure to absorb and frustrate NATO leaders in the months ahead.

The agreement between Europe and Turkey is important to European efforts to build a more credible defense and foreign policy. The European Union wants access to NATO assets to prepare its rapid-reaction force. Turkey has two reasons for objecting. First, there is the Ankara government's resentment of the way Brussels has treated its EU membership application. There is also concern over the use of those assets outside the alliance; Turkey worries that it may end up committing to deployments over which it has no say and in which EU and Turkish interests might diverge. After months of negotiations, diplomats announced that they had reached a deal in principle.

The second achievement was the announcement by Mr. Javier Solana, the EU's foreign-policy chief, that he had persuaded Macedonia's political leaders to resume political cooperation in a national-unification government. Although Mr. Solana deserves credit for his power of persuasion, NATO needed to be unified behind him if he was to have any clout. While it is hard to see who could object to a unity government, there is always room for disagreement in the murky world of Balkan politics.

There was also consensus on the NATO deployments in Bosnia. Despite indications that the United States would press for a cut in NATO troops deployed there, the foreign ministers concluded that major reductions were inadvisable, avoiding a possible split between Europe and the U.S. Defense ministers will review the 42,000-troop deployment when they meet in Brussels next week. There is still considerable skepticism in Washington about the wisdom of such deployments, but Europe is adamant that the U.S. should retain its presence.

Differences were more visible when NATO officials pondered expansion of the alliance. There is growing ambivalence about the wisdom of taking on new members, despite the eagerness of many former Warsaw Pact nations to join. Experience to date has been mixed. The Czech Republic, Hungary and Poland joined in 1999, but the general assessment is that they have performed below NATO's military norms.

Equally important are Russian objections to any expansion, which is viewed in Moscow as an attempt at containment. At its Vilnius meeting, the NATO Parliamentary Assembly endorsed a declaration inviting all European democracies that can contribute to collective security and whose membership would enhance regional security and stability to open talks. Russia boycotted that meeting, the first to be held on former Soviet territory, to avoid giving even tacit support to the membership hopes of the Baltic states of Lithuania, Latvia and Estonia.

Disagreements were most evident on the subject of ballistic missile defense, although in this case the proof is in what is not in the final declaration. The administration of U.S. President George W. Bush is committed to development and deployment of a missile defense system; Europeans disagree on both the need for such a system and its potential effects. Reportedly, the U.S. could not get its allies to agree on the need to mention a shared missile threat in the foreign ministers' declaration. In compensation, the final declaration makes no mention of the Antiballistic Missile Treaty, which was described in last year's declaration as a cornerstone of strategic stability.

The Bush administration won a similar victory on language concerning other arms treaties. In referring to the Comprehensive Test Ban Treaty, the declaration calls for maintaining existing moratoriums on testing; last year, NATO called for the treaty's early entry into force. At that time, the alliance said it would closely follow strategic arms-reduction talks and hoped they would strengthen the ABM Treaty. This year, the foreign ministers called for further arms reductions, but not necessarily through negotiations. That position approximates the U.S. call for a missile defense system and unilateral cuts in nuclear arsenals.

Diplomacy is the art of creative compromise, and NATO has produced some excellent examples in its final declarations. That willingness to find common ground will be increasingly important as the alliance squares off over these issues in the months ahead.