Regional security issues threaten to end the US-Russian partnership in security affairs before it is truly realized. Contradictions between the ideas of collective security and spheres of interest already have caused tensions in the partnership. Weapons of mass destruction are more readily available today and therefore regional conflicts potentially are more dangerous than ever. However, the partnership also has encountered difficulties in devising common strategies for dealing with the deadly threat of nuclear proliferation. If their partnership is to prosper, the two countries will have to work together to create a more predictable international order. This should be based on a better definition of the issues that Russia and the USA see in various types of regional conflict. US-Russian interests are engaged in regional disputes when weapons of mass destruction are a factor or where one or the other has special strategic, economic or historical connections with parties to disputes. There are, of course, many conflicts where neither Russia nor the USA are directly or immediately affected. Regional organizations that could help to contain or settle disputes are often pitifully unprepared for this. The UN remains the strongest of the organizations that deal with war and peace issues, but it has been stretched to the breaking point. Strengthening regional organizations is an essential but long-term task; US-Russian co-operation within the UN framework must be sustained if the UN is to survive the challenges to it.