It is often thought that a criterion is necessary to determine if a natural kind is real as opposed to an arbitrary division of nature. However, previous attempts to hash out a distinguishing principle have been wrought with troubles. A prominent way to distinguish a real from an unreal one is through a mind-independence criterion. However, each mind-independence criterion has its respective issues. In this essay, I will motivate the importance of a criterion to determine if a kind is real as opposed to unreal. I will analyze and propose various accounts of distinguishing criteria and ultimately conclude that, due to the pitfalls of each account, there is no completely sufficient criterion to distinguish the reality of a kind. However, Tahko’s mind-independence of unification principles is the best candidate for a criterion.