CEO hubris is a vital construct in research on the psychology of organisational decision-makers. Hubristic CEOs influence strategic decisions, from acquisitions to product and geographic market entry. To date, research has mainly focused on how and when CEO hubris impacts CEOs and their organisations. I offer a framework in which CEOs predisposed to inflated self-evaluation engage in behavioural processes that yield overconfident strategic decisions associated with hubris. The framework reviews and summarises how such evaluations stem from CEOs’ psychological and social circumstances. It then links inflated self-evaluation to the three drivers of over-confidence that are associated with hubris: over-estimation, or the tendency to exaggerate prospective outcomes; over-placement, or the tendency to rank one’s capabilities and situation ahead of others; and over-precision, or the tendency to issue unduly bounded or narrow forecasts which tend to be inaccurate. The framework is illustrated by the case study of Elizabeth Holmes, formerly founder and CEO of Theranos, who was lauded as a celebrity entrepreneur before being convicted of crimes associated with her hubris.