Traditional network models are the most frequently used tools for time analysis, yet they suffer from many limitations in modeling real-world projects. This chapter describes some of the issues that occur in projects but are not reflected in standard network models. It utilizes computer simulation technology to generate a similar and more contemporary view. Traditional project networks define an activity relationship structure as fixed; in practice, there can be situations where one path or another is taken depending on some probabilistic conditional. The simulation model will collect computed project status after each literation for the following: project completion date, status of any defined milestone and critical path activities. As project managers learn more about situations not handled by traditional networks, more pressure will be brought on the traditional models to conform. Traditional network models portray the project as a static series of linked activities, often with padded duration times.