在哲学的概念中，善意的概念（拉丁语：bona fides, 或 bona fide 即“善意的”）指真实的，诚挚的意图或信念，与行为的结果无关。与其相对的概念为“恶意”、“不诚实的”（“欺骗”）和“背叛”（“虚伪”）。

在法律上，bona fides指对于一个命题（或有一定数量的主张）的正确性或错误性，以及一系列行为的正直性和堕落性的心智或道德上的诚实和信念。作为一个法律概念，bona fides在公平相关的事务中尤其重要（见合同）。

Good faith (Latin:bona fides) is fair and open dealing in human interactions. This is often thought to require sincere, honest intentions or belief, regardless of the outcome of an action. While some Latin phrases lose their literal meaning over centuries, this is not the case with bona fides; it is still widely used and interchangeable with its generally accepted modern day translation of good faith. It is an important concept within law, philosophy, and business. The opposed concepts are bad faith, mala fides (duplicity) and perfidy (pretense). In contemporary English, the usage of bona fides (note the "s") is synonymous with credentials and identity. The phrase is sometimes used in job advertisements, and should not be confused with the bona fide occupational qualifications or the employer's good faith effort, as described below.