This document provides an overview of the evolution and dimensions of nuclear strategy and deterrence theory. It discusses key concepts of deterrence, how deterrence differs from compellence, and whether deterrence can stop nuclear weapons. It examines how NATO uses deterrence and whether NATO acts as a deterrent to Russia. The document also outlines four waves of deterrence research and suggests a potential fifth wave is emerging to address today's strategic challenges. It previews the themes that will be covered in the course, including historical, conceptual, and non-Western perspectives on deterrence against state and non-state actors across different instruments and domains.