On Tuesday 13th November, David Colver and Jonathan Swan of Operis ran a workshop on financial modelling attended by twenty boys. They explained that Operis builds financial forecasts for companies in order for them to be able to borrow money to finance large, and more recently, not so large projects. They explained the history of project finance and gave examples of many large infrastructure projects in particular that have been financed in the last four decades. The second half of the workshop explored a realistic case study which showed how spreadsheets could be used to optimise the finance of a project in order to keep both banks and shareholders satisfied. It was apparent how competitive the process would be when different organisations were bidding to run a particular rail franchise, for example. In two hours, the workshop explored significant ground and gave everyone real insights into the challenges of working in project finance.