Betting exchange markets, which offer person-to-person betting, have attracted increasing interest due to their similarities with financial markets and their growing economic importance. This paper presents SPORTSBET, an event-driven tool for the quantitative evaluation of betting exchange trading strategies. It was developed to specify, execute and back-test parameterised betting strategies for a wide range of sports. SPORTSBET allows the definition of betting strategies in an extended version of the UrbiScript language as sets of concurrent processes which make use of event-calculus-like operators. Strategy performance is quantified by synchronizing multiple real time or historical data streams with a dynamic market reconstruction.