This chapter provides an overview of the state of the art of Spain–North Atlantic Treaty Organization (NATO) relations. It explores Spain’s ambivalent posture: a middle-range power with limited ambitions and scarce defense expenditure, yet one of the most active players in NATO operations. The chapter examines an interesting, yet undervalued, scholarly debate about Spain’s visions of NATO. It traces the historical evolution of the country’s relationship with the transatlantic collective defense system. The chapter deals with the future of Spain–NATO relations, which do not seem to foresee any radical shift. Lacking a mature defense culture, and with its political elite unable to embark on a truly bipartisan approach on security issues, Spain’s defense policy continues to develop mainly through a path of institutional inertia. Geographical proximity, political relevance, and economic and social connections make North Africa “a strategic priority” for Spain’s foreign and defense policy.