This research-based book critically examines the complex interplay of power relations in decision-making in megaprojects. This book is tailored for academics, students, practitioners, clients, and policymakers and addresses a significant gap in understanding how formal and informal power influences decision-making. Through applying governmentality theory and narrative inquiry from thirty-nine interviews, this book presents over sixty-five detailed stories offering a series of real-life narratives that expose the diverse forms of power at play in megaprojects. The stories reveal how deviations from norms can significantly impact project outcomes. This book uncovers the complex web of power relations, institutional norms, and individual actions driving decisions.This book provides a framework illustrating four behavioural contexts, entrepreneurial, box-ticking, deception, and recklessness, as manifestations of megaproject decision-making, providing readers with a tool to understand and navigate the intricate power dynamics in megaprojects.Readers will benefit from practical insights and strategies for fostering conducive decision-making environments, tailoring interventions to promote constructive behaviours, and mitigating harmful actions. This book is a resource for anyone seeking to grasp the complexities of megaproject management in the context of power relations, shaping their decision-making leading to success.