Small states are survival artists. In a system shaped by power politics, the survival and proliferation of small states is a truly remarkable phenomenon. But what is the actual magnitude of this phenomenon and how can it be explained? What is the story behind the survival of small and weak states in a world of great powers? In this book, Matthias Maass investigates small state survival, proliferation and termination in the states system throughout its historical incarnations. Advancing existing scholarship, he re-focuses the discourse on vulnerability and provides an original long-term perspective on small state survival. His fundamental argument is that variations in the states system's main characteristics create significant changes in the system's hospitality toward the small state - and the friendlier the systemic environment, the better the chances for small state survival and proliferation. Ultimately, he shows that the remarkable upward and downward changes in the number of small states over the past three and a half decades are the result of major shifts in the states system, with all indications being that this story will continue far into the future.