How can intelligence agencies be held accountable without compromising their ability to act quickly and effectively? This book presents how, since 2017, Canada has reshaped its oversight of the CSIS and CSE intelligence services. It describes how the new oversight bodies - the NSIRA, the NSICOP, and the Intelligence Commissioner - work together to review, monitor, and guide intelligence operations. Using open-source reports and data, the book conducts case studies and international comparisons to evaluate whether these reforms have increased transparency and accountability while maintaining operational effectiveness. Addressing professionals, policymakers, and researchers, the book introduces an innovative performance review method tailored to intelligence work. It highlights the gains and growing pains of Canada’s oversight system and offers five practical reforms to improve it. Written in a clear, evidence-based, and policy-focused style, the book helps readers understand the real-world impact of intelligence oversight and how democratic values and national security can coexist.