Older adults are the least active population group in the US. Yet, research has shown that an increase in physical activity (PA) can have immediate and profound effects on cardiovascular health. Older adults who are active use significantly fewer health care resources, and with the increasing number of older adults in the US it is imperative to curb health care expenditure in this group. PEP4PA (Peer Empowerment Program 4 Physical Activity) is a multilevel intervention aimed at increasing physical activity levels in a population of low income and ethnically diverse older adults. It will be delivered in centers by trained older adults. Participants will work towards a daily increase of 2000 steps per day through self-paced incidental walking, peer led group walks, and attendance at existing center PA classes. They will also work on projects to increase opportunities to be physically active at their center or in the surrounding neighborhood.