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<div><p>We propose a framework in which interventions are described as situations affording the expression of certain personality traits to provide a systematic understanding of differential intervention response by personality traits. The goal of the present paper is twofold: 1) elaborate on the proposed framework, and 2) provide an initial test of this framework. We empirically tested this framework using data from a Randomized Controlled Trial (<i>N</i> = 176) that examined a smartphone-based intervention aimed at increasing future-oriented thinking and behavior, and assessed HEXACO personality traits. The results showed that more introverted and agreeable individuals profited most from the intervention. Although these results were not in line with our a priori predictions, they could be explained using the proposed situational affordances framework. This shows the potential of this framework in an intervention context, though more research and tests using different interventions are needed.</p><p><b>Trial registration:</b> The trial is registered in the Netherlands Trial Register number NL9671. Additionally, the hypotheses and analysis plan of the present study were pre-registered (AsPredicted #94684; <a href="https://aspredicted.org/95F_CDR" target="_blank">https://aspredicted.org/95F_CDR</a>).</p></div>