Seismic attributes are a great aid in both the qualitative and quantitative mapping of subsurface geologic features. Even before classical interpretation of picking horizons and generating maps begins, animating through appropriate seismic attribute volumes can quickly define the structural fabric and delineate major stratigraphic features. Seismic attributes have proven useful in almost every geologic environment, from clastics through carbonates to volcanic, and from normal faulting through wrench faulting to reverse faulting. Thus, seismic attributes facilitate recognition of depositional environments and enhance the recognition of seismic facies. Once calibrated at well locations, attributes can be used to identify seismic facies and provide information about both lithology and fluids, with or without the use of reference horizons. For this reason, seismic attributes form an integral part of most interpretation projects completed today. A complete book on seismic attributes, Seismic Attributes for Prospect Identification and Reservoir Characterization, has been published by SEG recently.