OBJECTIVE To investigate the effects of an individualized, home-based caregiver-training program for caregivers of elderly patients with dementia and behavioral problems. METHODS Using a randomized clinical trial in the neurologic clinics of two hospitals and a community care management center in northern Taiwan, we tested an individualized home-based caregiver-training program for managing behavioral problems, with referrals to community services and telephone consultation. Participants were patients with dementia and their caregivers (N = 129): 63 in the intervention group and 66 in the control group. The control group received only written instructions and social telephone follow-ups. Behavioral problems of elderly dementia patients were assessed by the Chinese version of the Cohen-Mansfield Agitation Inventory, community form. Family caregivers' outcomes were measured by the Agitation Management Self-efficacy Scale and the Preparedness and Competence Scales. These instruments were administered before the program and 2 weeks, 3 months, and 6 months afterward. RESULTS Family caregivers who received the individualized home-based training program had better preparedness (t = 2.72, df = 127, p <0.01), competence (t = 4.77, df = 126, p <0.001), and overall self-efficacy (t = 3.81, df = 127, p <0.001) at 3 months than those in the control group. Moreover, the growth rate by treatment interaction effect was significant for caregiver competence (t = 2.25, df = 127, p <0.05) and overall self-efficacy for managing behavioral problems (t = 2.16, df = 127, p <0.05). The probability of physically aggressive behavior for patients in the intervention group decreased from 0.27 to 0.12. CONCLUSIONS Our individualized home-based caregiver-training program improved caregivers' preparedness, competence, and self-efficacy for managing problematic behaviors and decreased physical aggressiveness of elderly patients with dementia.