Abstract The demands that reservoir characterization places on seismic data far outweigh those of traditional structural interpretation. Because of this, gather conditioning is seen by many as a prerequisite to prestack inversion. This paper discusses three conditioning processes—signal/noise (S/N) improvement, stretch removal, and reflector alignment. It then seeks to document the improvements that these processes achieve in the gathers and in prestack inversion. Specifically, the gathers were measured for AVO fit using a 2-term Shuey equation and found to be improved by 20%. A comparison of wavelets extracted from each angle stack found the high frequency limit of stable phase to have increased from 30 Hz to 50 Hz. The far angle stack seismic/synthetic inversion residuals showed a 43% drop in amplitude and completely different frequency and reflector character following gather conditioning. Finally, the acoustic impedance (AI) vs. shear impedance (SI) cross-plot showed a much more compact signature that allowed more definitive lithology and pay discrimination. Conversely, the raw data cross-plot contained noisy data that erroneously entered into the area of the cross-plot where the pay signature lay. Geobodies captured from improperly conditioned data are thus (1) inflated in size by 62%, and (2) have lower impedances than is justified from well control. These errors, in turn, would lead to incorrect rock property (hydrocarbon saturation and porosity estimation) and reserve estimations.