Imagery rescripting (ImRs) is a therapeutic intervention that is known to reduce distress from negative memories. It uses imagination to change the course of events in the memory, creating a more favourable outcome. Despite its proven effectiveness in treating various disorders, the underlying mechanism driving this reduction in distress remains unclear. This study examines the effect of pre-treatment self-efficacy on ImRs outcomes, with a particular focus on reducing memory-related distress. Additionally, this study tested whether this effect is mediated by participants' ability to fulfil action tendencies and needs during rescripting. The study was conducted in a non-clinical population using a single ImRs session.