Whereas realism deals mainly with security and material power, and liberalism looks primarily at economic interdependence and domestic-level factors, constructivism most concerns itself with the role of ideas in shaping the international system; indeed it is possible there is some overlap between constructivism and realism or liberalism, but they remain separate schools of thought.
Bila realisme mementingkan keamanan dan kekuasaan materi, dan liberalisme mementingkan interdependensi ekonomi dan faktor-faktor dalam negeri, konstruktivisme lebih mementingkan peran pemikiran dalam membentuk sistem internasional; sebenarnya ada kemungkinan tumpang tindih antara konstruktivisme dengan realisme atau liberalisme, namun ketiganya tetap terpisah.