This document summarizes the experience of National Australia Bank implementing a risk-based testing methodology. The methodology provides a formalized approach to evaluating requirement risks and using those risks to plan testing efforts. It involves workshops to determine likelihood and impact of failures for each requirement. This information is then used to prioritize testing order and guide the scope of testing, focusing on high-risk areas first. The methodology aims to find important problems quickly while reducing low-value testing and justifying testing costs and efforts to stakeholders based on business and technology risks.