This research is studying the effectiveness of carbon dioxide (CO2) flooding in a mature reservoir to identify and develop methods and strategies to improve oil recovery in CO2 floods. The objective of the project is to develop a methodology for improving sweep efficiency and reducing CO2 utilization rates by performing a detailed post-mortem on a mature CO2 project that relates actual reservoir performance with predicted performance. Knowledge gained from this detailed analysis will yield improved operating practices that will serve as a guide to improving oil recovery in active CO2 floods and as a strategy for implementing new CO2 floods.