A range of psychiatric disorders are characterised by impairments in episodic future thinking (EFT), and particularly simulating specific, spatiotemporally-located future events. No study has examined whether training can lead to sustained improvement in specific EFT. In this study, participants (N = 60; M age = 31, SD = 13.2) were randomized to a two-session, group-based future thinking program (Future Specificity Training; FeST) or wait-list. At follow-up the training group, relative to wait-list, showed large, statistically-significant improvements in the ability to mentally simulate specific EFT (d = .82), increases in detail (d = 1.32), use of mental imagery (d = 1.32), anticipated (d = 1.78) and anticipatory pleasure (d = 1.07), perceived control (d = 1.20), and likelihood of occurrence (d = 1.09). Some effects were also observed on positive, generalised future selfstates. In the context of inherent limitations of subjective reporting in trials, this study provides evidence that EFT specificity can be enhanced, and the effects of FeST indicate a possible avenue to disrupt psychopathological processes.