Both the 21st Century Cures Act and the PUDUFA VI legislations emphasize on complex innovative designs, which require simulations to understand the design operating characteristics, statistical properties, and operational features. This session will review and discuss the issues related to any complex trial design that we need to simulate the trial to understand its full behavior. Additionally, it will discuss analyses that are complex enough so that we likely need simulation for deeper understanding of the models. Examples of complex analyses include using hierarchical analyses and historical data will be given. A group of speakers and panelists will discuss opportunities and challenges relative to complex innovative designs and analyses in medical product development.