Since the first description of prion diseases, great effort has been made toward comprehending this new paradigm in biology. Despite large advances in the field, many questions remain unanswered, especially concerning the conversion of PrP^C into PrP^Sc. How this conformational transition evolves is a crucial problem that must be solved in order to attain further progress in therapeutics and prevention. Recent developments have indicated the requirement for partners of the prion protein in triggering the conversion. In the present review, we will explore the interaction of PrP with some of its most intriguing partners, such as sulfated glycans and nucleic acids. These molecules seem to play a dual role in prion biology and could be fundamental to explaining how prion diseases arise, as well as in the development of effective therapeutic approaches.