ADAP is a finite element program capable of performing linear static and dynamic analysis of arbitrary arch dam-foundation systems. Most of the logical features and many of the subroutines of the computer program SAP are utilized in this program. Special features primarily associated with preparation of input data are incorporated to make it more suitable for arch dam analysis. Three different element types are included in the program; these are considered to be the most suitable in this application. The program is organized in such as way that, if desired, new elements can be included easily. A finite element mesh is automatically generated from a minimum amount of input information. In each problem any one of the following types of analysis can be requested: (1) static analysis - the program is capable of handling an arbitrary combination of gravity, water pressure, and temperature loading conditions, and concentrated loads at any node; (2) evaluation of natural frequencies and mode shapes - if these are not available for input they are automatically evaluated as part of (3) or (4); (3) response history analysis - using a step-by-step integration scheme assuming the accelerations to vary linearly within each time step; and (4) response spectrum analysis - which results in estimated maximum values for displacements and stresses.