Answer: Informants seldom agree perfectly in their reports of people’s problems. One reason for obtaining ratings of similar items from multiple informants is to identify both the agreements and disagreements between particular informants. If specific disagreements are found, these can be investigated to determine whether the informants differ in their judgments of similar behavior or whether they differ in what they see or in their willingness to report problems that they see. Besides identifying specific agreements and disagreements, the Ages 18-59 Module displays Q correlations between informants. The Q correlations can identify exceptionally low levels of agreement that should then be a focus of clinical inquiry in their own right.