A description of how reservoir simulation is being used to quickly and easily add confidence to estimated reserves additions from new well drills (i.e. location, vertical vs. horizontal, etc.), well workovers (i.e. stimulation treatments), and reservoir recovery schemes versus conventional methods (i.e. decline curve analysis, material balance, volumetrics, analogous well/reservoir behavior, recovery factors, etc.) by way of a live demonstration of creating a reservoir model, running the model, and visualizing/using results from the model using CMG’s user-friendly, window-based, software and 3D immersion technology. The benefits of reservoir simulation over conventional reservoir engineering analysis methods have been known for many years, however its usage has traditionally been limited to the ‘high dollar/high profile’ reservoirs due to previous limitations in hardware (i.e. you had to have a UNIX-based computer), software (i.e. it was expensive, slow and difficult to use), and manpower resources (i.e. extensive experience to use old-style simulation software). Over the past few years, an evolution in the ease of use of reservoir simulation software has transformed the model creation process from a tedious, time consuming, text-editing exercise to a quick and very easy-to-use, interface-guided process. The incredible runtime speeds now possible in the “Wintel” environment (i.e. Intel-based PCs running Windows OS) has facilitated the movement of reservoir simulation software from the UNIX to the now-ubiquitous WINDOWS based desktop computing. Production and ultimate recovery forecasts for new drill prospects can now be performed in hours or days rather than in weeks or months, making reservoir simulation a viable tool in the Decision Analysis process for selecting the most economic drilling projects. Applications to existing fields that require history-matching of previous performance can now be accomplished in days or weeks, allowing reservoir simulation-based forecasts to be part of the Decision Analysis process for well workovers and alternative reservoir operations/recovery methods. The demonstration will show how easy it is to build reservoir simulation models from scratch (starting from existing maps and well data), how to run those models, how to analyze/visualize the results from those models (using 3D immersion technology), and how to export the model results to economic analysis programs. Two examples applications will be presented: (1) a new drill prospect example showing the impact of well location, completion type, lift method, fluid contact depth and drive mechanism on total EUR, and (2) an existing reservoir showing the impact of waterflooding vs. gas injection vs. drilling new horizontal wells on incremental EUR.