Our critical commentary explores the overlaps and divergences between Rational Emotive Behaviour Therapy (REBT) and contemporary mindfulness practice and considers whether the approaches could be integrated and applied effectively within two high performance settings in particular: sport and business. It highlights how REBT and mindfulness share similar philosophical positions on the causes of emotional disturbance, on the importance of acceptance, and on cultivating self-awareness to respond healthily and adaptively to adverse events. It also acknowledges diverenges relating to REBT and mindfulness’ respective positions on judgement of thoughts, an emphasis on the present moment, and meditative practice. We observe that by cultivating metacognitive awareness—a capacity to impartially observe thinking—mindfulness may help individuals in high performance settings to see more clearly how their beliefs influence their emotional, cognitive, and behavioural outcomes. Mindfulness could thus potentially aid an individual’s transition from intellectual insight to emotional rational insight within an REBT framework. Moreover, appropriately integrated mindfulness practice alongside REBT-based work may help individuals within high performance settings, and beyond, to cultivate a mindset that is grounded in the present, less distracted and more task focused, potentially enhancing performance outcomes.