Although creativity can assume many forms, one especially important type is creative genius, a guise of Big-C creativity rather than everyday little-c creativity. Creative geniuses make pervasive and enduring contributions to human civilization. This chapter reviews what research has learned about these superlative creators. The review begins by discussing the diverse domains to which creative geniuses contribute their masterworks. This discussion includes a treatment of the highly versatile polymaths. The review then turns to the correlates of genius across different creative domains, including both dispositional and developmental factors. From there, the overview looks at how to grade geniuses along a quantitative scale. The two primary measures are achieved eminence and creative productivity, where the latter is the main determinant of the former. That leads to a summary of the variables underlying creative output. Yet that summary requires scrutiny of the processes behind genius-grade creativity. Although a huge inventory of processes (and procedures) have been identified, all share two basic properties: All creativity is combinatorial and selectionist, meaning that the creator must be able and willing to generate combinations without any prior knowledge of their utility, whether at the individual level or at the level of the creator’s field. The review concludes with recommendations for future research.