Abstract: The Diabetes Prevention Program (DPP) is a 12-month behavior change program designed to increase physical activity and improve dietary patterns among patients at risk for Type 2 diabetes, in order to facilitate modest weight loss and improve cardio-metabolic profiles. It is unknown whether baseline patient activation is related to increased DPP uptake, and whether DPP attendance leads to subsequent improvement in patient activation. We analyzed data from 352 adult participants in the Prediabetes Informed Decisions and Education (PRIDE) trial of shared decision-making (SDM) in diabetes prevention, collected from November 2015 through September 2017. PRIDE participants completed baseline and 4-month follow-up surveys, including the Altarum Consumer Engagement (ACE) Measure™ of patient activation. We tracked DPP attendance over 8 months using data from partnering DPP providers. In multivariate models, we measured whether self-reported baseline activation was associated with DPP “uptake” (1+ session attended) or DPP “attendance” (9+ sessions). We also examined whether DPP attendance was associated with change in activation at 4-months follow-up. We did not find an association between baseline activation and DPP uptake or attendance. However, we did find that DPP attendance was associated with an increase in the overall ACE score (6.68 points, 95% CI 1.97–11.39, p = 0.005) and increased activation in 2 of the 3 ACE subscales (Commitment and Informed Choice). Our finding of increased patient activation with DPP attendance suggests a mechanism for the improved health outcomes seen in DPP real-world translational studies. This work has important implications for diabetes prevention and other behavior change programs.