We developed the Headington Institute Resilience Inventory as a psychometrically valid, multifactored self-report measure to identify dimensions of resilience for international aid workers. We define resilience as the capacity to adapt during traumatic incidents so that one not only just survives but survives well. By utilizing a dynamic approach to resilience to predict this adaptive capacity, we aim to identify dimensions that could lead to personalized protective training exercises, essential because of the work in areas of constant tension where there is a high risk of exposure to traumatic events. From 84 theory-driven items, through exploratory and confirmatory factor analyses with 2 samples of aid workers ( ns = 724 and 829), we identified and refined the most robust factors. Our resulting 7-factor, 33-item measure had αs greater than .69 for all factors, test–retest reliability coefficients between .79 and .94, and an estimate of composite scale reliability of .82. The findings are congruent with social–cognitive theories of resilience, which provide a plausible understanding of resilience as a multifaceted, dynamic construct. Although continued research is needed to fully validate the construct of resilience, this framework identifies dimensions of protective assets that are believed to be amenable to development, thus providing aid workers with a working definition of resilience.