Broad areas of study within liberal international relations theory include: The democratic peace theory, and, more broadly, the effect of domestic political regime types and domestic politics on international relations; The commercial peace theory, arguing that free trade has pacifying effects on international relations.
Bidang studi dalam teori hubungan internasional liberal meliputi: Teori perdamaian demokratis dan efek jenis rezim politik dalam negeri dan kebijakan dalam negeri terhadap hubungan internasional; Teori perdamaian perdagangan: Perdagangan bebas memiliki efek mendamaikan dalam hubungan internasional.