Sphere of influence is a term frequently used in political parlance, yet it remains uncontested in International Relations. Laden with pejorative connotations, the term is often used to criticise Russian foreign policy. Drawing on the work of the English School, the author discusses the concept of sphere of influence in relation to international order and questions of justice. She also explores the work of Carl Schmitt, E.H. Carr and Walter Lippmann, among others, who saw spheres of influence as exponents of a regional solidarism. The author provides further insights into the history of the concept through an analysis of the Cuban Missile Crisis as a reflection of the Cold War at large. Lastly, she discusses Russian analysts' ideas on spheres of influence in light of the pluralistsolidarist debate of the English School. In challenging the pejorative associations of sphere of influence, the thesis lays the groundwork for redefining the concept in International Relations.