The document provides examples of case studies where Pro Bono O.R. has been applied. The first case study describes how volunteers analyzed data and built a simulation model to recommend new staff shift patterns for a crimestoppers call center, improving performance without increasing costs. The second case study discusses how volunteers identified process improvements and value-adding activities for a charity matching volunteers to organizations. The third case study outlines how volunteers helped a youth venture define risks to sustainability and create a risk management plan.