In honesty, without taking unfair advantage.
In human interactions, good faith (Latin: bona fides) is a sincere intention to be fair, open, and honest, regardless of the outcome of the interaction. Some Latin phrases have lost their literal meaning over centuries, but that is not the case with bona fides, which is still widely used and interchangeable with its generally-accepted modern-day English translation of good faith. It is an important concept within law and business. The opposed concepts are bad faith, mala fides (duplicity) and perfidy (pretense). In contemporary English, the usage of bona fides 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.