["Japanese Psychological Research, EarlyView. ", "\nAbstract\nAlzheimer's disease (AD) involves deficits in multiple cognitive domains, particularly memory and executive function. This study explored the effectiveness of an individual cognitive stimulation program in older adults with moderate AD. A multicenter, parallel, two‐arm, single‐blind randomized controlled trial was conducted with 80 older adults. Participants were randomly assigned to either the individual cognitive stimulation group (n = 39, 24 sessions, twice a week for 12 weeks) or the treatment‐as‐usual group (n = 41). Cognitive outcomes—global cognition, memory, and executive function—were assessed at baseline, post‐intervention, and at 12‐week follow‐up. Analyses were conducted using linear mixed‐effects models under an intention‐to‐treat framework, complemented by repeated‐measures analysis of variance. Results showed a significant Group × Time interaction for free recall memory and for Alzheimer's Disease Assessment Scale—Cognitive Subscale “recall of test instructions,” with a marginal interaction for “comprehension of spoken language.” However, no significant between‐group differences were observed at any time point. No other significant between‐group differences over time were found using linear mixed‐effects models or repeated‐measures analysis of variance. Although some benefits were identified, the reduced responsiveness in more advanced AD stages highlights the challenges of cognitive intervention at this phase.\n"]