Newly enacted Federal regulations have focused increasing attention on the use of psychoactive drugs and on the treatment of disruptive behavior in the nursing home. To study the interaction between resident behavior and staff distress in nursing homes, we measured the frequency of seven types of behavior problems among 346 residents of intermediate care facilities who were receiving some form of psychoactive medication. Nurses were interviewed on two shifts to determine their perception of the frequency and severity of each behavior in each patient as well as the level of distress it caused among caregivers. The most common behavior problems noted were agitation (42%), withdrawal (33%), and noisiness (27%). Only half of the reported instances of behavior disorders were considered distressful by nursing home staff. While physical abuse caused distress 92% of the time and verbal abuse 90% of the time, wandering was seen as distressful to staff only 50% of the time. Nearly a third of "wandering" patients were restrained; they produced less distress than non-restrained wanderers. There was substantial disagreement, ranging from 6% to 22% for individual residents, over the presence of distress-causing behavior, although day and evening nursing shifts rated the frequencies of behavior and the degrees of distress equally on average. Residents with higher cognitive function were less likely to cause distress for all behaviors, except for verbal abuse where the reverse was true. Age and dependency in activities of daily living were not associated with problematic behavior or staff distress. These findings indicate that the existence of "problematic" behaviors in a given resident is often perceived differently by different staff, and its impact on staff also differs widely.