Interest-relative invariantism is the view that practical interests encroach upon knowledge. In other words, the more that is at stake for S, the harder it is for her true belief to be an instance of knowledge. Russell and Doris argue that IRI theorists are committed to indifference being knowledge-making feature of IRI, where knowledge comes easier for subjects the less they care. In this paper, I explain why indifference cases are problematic and which assumptions about IRI generate them. I then (...) argue IRI theorists can immunize themselves from indifference problems by grounding practical interests in either Aristotelianism or a restricted form of Humeanism, both of which link practical interests to some conception of well-being. I then argue that besides solving indifference problems, these approaches present a reasonable conception of practical interests, while also saving IRI theorists from abandoning plausible theses about knowledge. (shrink)