ABSTRACT This paper presents the use of hydraulic interwell connectivity concepts to characterize the reservoir for waterflood performance evaluation. These hydraulic interwell connectivity concepts are presented in terms of two indices: The Interwell Flow Capacity Index (IFCI) and the Hydraulic Interwell Connectivity Index (HICI). This approach utilizes the reservoir flow capacity and production/injection performance data to calculate the IFCI and HICI. The spatial distribution and correlations of these indices are useful to evaluate the reservoir characteristics for waterflood design and performance analysis. A Colombian (South America) sandstone reservoir in La Cira Field is used to illustrate the application of these concepts.