The Alabama Transportation Infrastructure Model (ATIM) is a discrete event simulation of major transportation routes. The model is currently being validated; however, due to limited data and projected changes in traffic patterns, common validation methods (comparison to real-world figures and utilizing historical data to forecast future trends) are impractical. Therefore, an alternative validation approach was developed, using a scenario planning technique known as extreme-world view that allows model developers to test a wider range of model inputs than using limited current or historical data. The model’s response to a range of scenarios indicates it tracks expected real-world performance well.