Contemporary radical right political parties, organisations, and members represent a serious threat to society. While a considerable amount of research has assessed the threat they pose and how we might respond to it, little attention has been paid to the epistemic activities of members of the radical right and how they may restrict the circulation of epistemic goods necessary for the development and modification of effective responses. In this thesis, I explore the possibility that members of the radical right suffer epistemic injustice. I maintain that there is a strong reason for affirming this possibility according to how members of the radical right engage and are treated during epistemic activities. Additionally, I provide insight into why this epistemic injustice is significant and how we might address it. Epistemic injustice is a relatively new theory in philosophy. By combining three spheres of philosophy, namely the epistemic, the political, and the ethical, epistemic injustice investigates how common epistemic practices may function such that injustice is inflicted on people bearing particular social identities. That is, people are unfairly undermined in their capacities as knowers, mistreating them in relation to knowledge, understanding and participation in communicative practices. I argue that members of the radical right suffer two forms of epistemic injustice. Firstly, they suffer testimonial injustice when their credibility is determined and subsequently diminished because of the negative identity-prejudicial stereotype (NIPS) that overlooks the ideological features on which the radical right and the extreme right differ and the framework set out to reflect them. By applying Iris Marion Young's social connection model (SCM), I locate those causally connected to the testimonial injustice as being responsible for addressing it. Secondly, members of the radical right suffer hermeneutical injustice because the collective epistemic repertoire is not receptive to the requisite epistemic resource that captures their societally pessimistic and nostalgic worldview. By utilising Young's SCM, I identify those who contribute to maintaining the structural phenomenon that carries the hermeneutical injustice as being responsible for addressing it. Finally, I investigate what follows from the epistemic injustice the radical right suffers in terms of remedial action. I recommend that in order to address the epistemic injustice they suffer, we ought to address the structural dimensions that carry it. I maintain that my investigation into the epistemic injustice that I argue members of the radical right suffer is significant because of the tripartite harms it causes. Specifically, those who suffer epistemic injustice and those complicit in the perpetration of epistemic injustice suffer because of it, while the epistemic system is damaged by it. Whilst the harm that those subject to and complicit in the perpetration suffer is of interest, I insist that the damage to the epistemic system is a crucial concern for self-interested reasons. Essentially, the epistemic injustice that the radical right suffers restricts the circulation of epistemic goods pertaining to their worldview and ideology. I propose that this restriction of epistemic goods can indirectly cause practical disadvantages for everyone who participates in the epistemic system when developing and modifying effective responses to the radical right. Therefore, impeding our ability to challenge the radical right appropriately and respond to the seeds of hate and division they sow within society.