Corruption is deeply entrenched in Papua New Guinea (PNG)'s administrative and political systems. However, despite a litany of studies on mainstream institutional causes of corruption in PNG, there has been little focus on the role of PNG's strong social networks and reciprocity systems in embedding corruption within state institutions. Through a review of literature pertaining to patron-client politics and corruption, I argue that PNG's informal systems of reciprocity, the wantok and big man systems, have systematically exacerbated corruption through practices of patron-client politics.