Fundamentals of Diplogยฎ Analysis updates and ex- pands upon material presented in the Dresser Atlas publication Diplogยฎ Analysis and Practical Geology, last published in 1983.Dip measurements have become a widely recognized source of information for describing sedimentary struc- ture and various tectonic events. Effective use in field development has also become widely accepted in re- cent years.Other wireline measurements, integrated with dip data, often provide descriptive evaluations for delineation of reservoir development trends, reservoir geometry, and depositional environment, enabling reservoirs to be exploited more efficiently.