ACT® Tessera® is a comprehensive assessment system designed to measure five social and emotional skills. Due to its many desirable features, the ACT Tessera development team adopted the Big Five taxonomy, the dominant personality trait model, as the organizing framework. Researchers factor analyzed personal trait-related adjectives identified in the English language dictionary, and this ultimately led to five replicable factors. A key advantage of the Big Five framework is that it optimizes bandwidth and fidelity; that is, it allows for the summary of a large amount of information while simultaneously allowing for some nuanced individual difference description. The ACT Tessera skills have been aligned to the Big Five previously (ACT, 2018). Here the authors present the alignment between the ACT Tessera skills and the five core social and emotional learning competencies adopted by the Collaborative for Academic, Social, and Emotional Learning (CASEL). The authors concluded that the ACT Tessera skill framework has all the advantages of the Big Five personality model, including decades of empirical backing, and simultaneously aligns with CASEL's core competency framework, which is arguably the most influential social and emotional skill framework in the US.