This book explores the factors that account for military neutrality as a security strategy for small states. Through comparing the cases of Serbia and Sweden, who have both come to define their security policies in identicial terms of military neutrality/non-alignment, the book introduces a novel conceptual framework that is built against existing knowledge found in the small states and military neutrality literature. Drawing on different theoretical frameworks, the model explains why certain small states choose to stay outside of military alliances in the twenty-first century. The author then applies the new model to the two selected case studies.