A culturally tailored lifestyle program with ongoing support produced greater cognitive improvement than flexible health guidance alone. Across 11 Latin American countries, older adults at risk of dementia improved their memory and thinking through lifestyle programs adapted to local cultures. The Alzheimer’s Association-funded Latin American Initiative for Lifestyle Intervention to Prevent Cognitive Decline (LatAm-FINGERS) tested two programs that combined physical activity, healthier eating, cognitive training and social engagement. The 539 participants assigned to the Systematic Lifestyle Intervention (SLI) received sustained coaching and supervision. The 526 people in the Flexible Lifestyle Intervention (FLI) received general lifestyle guidance and periodic health education.