Based on recent lexical studies across various languages, Honesty-Humility has been suggested as a sixth basic factor of personality. Specifically, according to the HEXACO Model of Personality, Honesty-Humility represents individual differences in active cooperativeness—operationalized via the facets sincerity, fairness, greed avoidance, and modesty. Herein, research corroborating Honesty-Humility as a basic personality factor is summarized and supplemented with an overview of the broad array of criteria this factor has been shown to influence. In addition, we briefly touch on aspects that are still understudied concerning Honesty-Humility, especially in terms of its biological basis, development, and broader societal consequences.