Recent world events have shone a spotlight on the social and structural injustices that impact the lives, health, and well-being of individuals and communities under threat. Dietitians should be well positioned to play a role in redressing injustice through their individual and collective “response abilities”, that is, the combination of responsibility for and ability to be responsive to such injustices due to the varying privilege and power that dietitians have. However, recent research shows that dietitians report a lack of knowledge, skill, and confidence to take on such roles, and that dietetic education includes little knowledge- or skill-based learning that might prepare dietitians to do so. This primer aims to introduce readers to concepts that are fundamental to socially just dietetics practice, including privilege, structural competence, critical reflexivity, critical humility, and critical praxis. We assert that when implemented into practice and used to inform advocacy and activism these concepts enhance dietitians’ individual and collective response ability to redress injustice.