Millions of Americans have diabetes or prediabetes, for which regular physical activity can reduce risks of unfavorable outcomes of these conditions. This study will test the effects of an evidence-based intervention in the primary care setting on increasing physical activity among these individuals. If effective, it can be broadly implemented in primary care.

Inclusion Criteria:

Able to speak English or Spanish, Inactive defined as less than 30 minutes of MVPA per week, Prediabetes or diabetes not prescribed insulin, Kaiser Permanente member for at least 12 months, Receives primary care at the Fontana Medical Center, Body mass index between 18.5 and 40 kg/m2,

Exclusion Criteria:

Current use of insulin, Cardiovascular event in the past 6 months or other condition that limits physical activity, Pregnancy, breastfeeding or planning pregnancy in next 2 years, Current participation in another clinical trial or research study, Plans to move out of the area in next 2 years,