Purpose: Aggression continues to challenge caregivers of persons with dementia, and identification of foci for effective interventions is needed. The purpose of this study was to examine the influence of (a) the resident characteristics of depression, communication, and cognition and (b) behavior management strategies on aggression in a group of older nursing home residents (N = 405) with evidence of dementia. Design and Methods: This cross-sectional correlational study examined the association of resident characteristics and behavior management strategies with bivariate aggression, physical aggression, and verbal aggression, using hierarchical regression. Results: Main findings are that impaired communication is associated with all forms of aggression, depression with physical aggression, and disorientation with verbal aggression. A 3-month prior pattern of antipsychotic drug use was consistently associated with all forms of aggression and physical restraint use with physical aggression. Most of the explained variance was attributable to antipsychotic drug use. Implications: The separate explanatory models for physical and verbal aggression indicate that these may be unique entities with different foci for treatment. These results provide evidence that aggression persists despite antipsychotic drug use and that further mental health interventions might be targeted at compensating for impaired communication and the treatment of depression to improve the mental health of nursing home residents with dementia. (Contains 4 tables.)