A rich literature exists on computational methods based on wave equations for seismic imaging and earth-parameter estimation. Somewhat lost in the advance to progressively more sophisticated computational techniques are the intuitive ideas with roots that reach back to Hagedoorn and are based on ray theory, the geometry of data, and the geometry of wave propagation. In Seismic True-Amplitude Imaging (SEG Geophysical Developments Series No. 12), the authors demonstrate that those simple ideas also lead to a broad description of the structure of the earth's interior and the changes in medium parameters across reflectors. Demonstrations in the open literature of the efficacy of their methods abound. Now those ideas have been collected and reorganized. The book provides a pictorial presentation of the basic principles of Kirchhoff-type imaging and proceeds to a comprehensive treatment of its kinematic and dynamic aspects. The text is a valuable addition to the library of anyone interested in the theory and practices of seismic data processing for imaging and parameter estimation with all its attendant processes.