Purpose: This study evaluated the longitudinal influence of an individualized evidence-based psychoeducational intervention for caregivers on frequency of behavioral symptoms in persons with dementia (PWD) and caregiver reaction to these symptoms. The intervention included information about the disease process using Progressively Lowered Stress Threshold (PLST) content and a family meeting based on Mittelman’s New York University Intervention. Method: A quasi-experimental study design was implemented. The Revised Memory and Behavior Problems Checklist was administered to N = 127 caregiver/care recipient dyads at baseline, 6, 12, and 18 months follow-up. All caregivers were enrolled in the intervention at baseline and followed over 18 months. Linear mixed models were developed to evaluate effects on frequency of behavioral symptoms in PWD and caregiver response. Results: The most frequently occurring behavior was memory problems, although depressive behaviors produced the most negative caregiver responses. Between baseline and 6-month follow-up, there was a significant decrease in frequency of behavioral symptoms. Overall, there was a significant decrease in caregiver’s reaction to behavioral symptoms from baseline to 18-month follow-up.