In this original work, Miranda Fricker reveals the ethical and political aspects that underlie our way of knowing and understanding and is committed to redirecting our epistemic behavior towards a field of rationality and justice. An epistemic injustice occurs when the ability of a subject to transfer knowledge and make sense of their social experiences is nullified. Fricker analyzes and makes visible the error that is committed -and the consequences that it entails- when the discourse of a subject is discredited for reasons beyond its content. The author determines two types of epistemic injustice: the one that occurs when an issuer is discredited due to the prejudices that his audience has - the testimonial injustice -; and the one that occurs when a collective is unable to understand the social experience of a subject due to a lack of interpretive resources, placing it in a disadvantaged situation and of reduced credibility -the hermeneutical injustice. The characterization of these two phenomena sheds light on a myriad of issues, such as social power, prejudices, reason or the authority of a discourse, and reveals the intrinsic ethical traits in our epistemic