Abstract
Overwhelming evidence from all over the world confirms that needle exchange programs (NEPs) in widely varied forms have value in prevention of HIV infection among injecting drug users (IDUs). Unfortunately, the United States has relatively few active NEPs because of political opposition to adoption of any policy that would give the appearance of condoning use of illegal drugs. Some additional opposition comes from the affected communities themselves. NEPs that assiduously construct links with affected communities have highest probabilities of effectiveness. Studies of NEPs, with some notable exceptions, still lack anthropological evaluations of their impact, and this deficiency needs more attention in future efforts to frame, implement, and evaluate NEPs.