ObjectivesInitiating and maintaining physical activity presents the individual with challenges of inconvenience, discomfort, and counteractive energy. Addressing these challenges requires an intervention that elicits motivation to engage in this activity, minimizes the direct relationship between unwanted internal experiences and inaction, and is also in itself accessible and convenient. Accordingly, this study investigated the efficacy of a self‐managed Acceptance and Commitment Therapy (ACT) intervention delivered viaDVDand tailored for physical activity initiation.Design and methodsFifty‐nine minimally active community participants were randomly allocated to receive a 12‐week pedometer‐based walking programme, or the same walking programme with the additional provision of theACT DVD. The primary outcome was overall physical activity level (assessed at baseline and post‐intervention), and the secondary outcome was pedometer‐assessed step count (measured at 4‐weekly intervals throughout the intervention period).ResultsParticipants who received theACT DVDachieved a significantly greater increase in physical activity levels post‐intervention, were more likely to achieve the goals specified in the programme, and reported a higher average step count than participants who received the walking programme in isolation.ConclusionsTheACTintervention, delivered viaDVDfor the promotion of physical activity, proved a simple, efficient, and accessible method to encourage positive short‐term increases in an important health‐promoting behaviour.Statement of contributionWhat is already known?ACTinterventions can increase physical activity levels through augmenting initiatory self‐regulatory control.Face‐to‐face delivery presents challenges of accessibility and feasibility for community implementation.There is a need for effective interventions that maximize impact while minimizing inconvenience.What does this study add?Supplementing a walking programme with a self‐managedACT DVDproduced significant increases in physical activity.TheACT DVDis a convenient, accessible, and potentially cost‐effective approach to physical activity initiation.ACTlends itself to implementation as a self‐managed electr