The presence of the bacterial genera Corynebacterium and Dolosigranulum has consistently been associated with a healthy upper respiratory tract (URT). Commonly occurring together in the nasopharynx of healthy children, the role of these commensal organisms in nasopharyngeal health is unknown, as few studies have sought to determine whether they actively contribute to maintaining a healthy state. We recently identified Corynebacterium pseudodiphtheriticum and Dolosigranulum pigrum as the major nasopharyngeal species associated with resistance to recurrent ear infections, via 16S rRNA gene sequencing and metagenomics. Using in vitro bacterial interference assays, we observed a reduction in the growth of Moraxella catarrhalis - one of the three major otopathogens - in the presence of C. pseudodiphtheriticum. Further in vitro and in vivo studies of the interactions between commensal C. pseudodiphtheriticumandD.pigrumstrains,URTpathogens, and the human host will help to clarify their role in nasopharyngeal health. If they play a protective role, these organisms are promising candidates for the development of a probiotic therapy for the treatment or prevention of URT diseases in children.