RecruitingBehavioural interventionWalk On! National Council on Aging Innovation LabThis is a multi-site, one-arm type-2 hybrid-effectiveness implementation trial. The goal of this clinical trial is to learn if the Walk On! program helps prevent falls in older adults who have trouble moving around or feel socially isolated. Researchers want to know: 1. What are the best ways for organizations to offer the Walk On! program and keep it running for older adults in their community? 2. Does Walk On! help prevent falls in older adults? Older Adult Participants will: 1. Join group walking sessions led by a trained facilitator 2. Meet twice a week for 12 weeks (24 sessions) 3. Take part in simple tests before and after the program to see if there are any changes in older adults' function, confidence in not falling, or loneliness.