The high accuracy achievable using space techniques (VLBI, SLR, GPS) requires rethinking of the theoretical foundations of deformation analysis to be applied. If the results of a deformation analysis are to be useful as initial data based on physical or dynamic models, which generally can be assumed, they have to refer to the physical surface of the Earth (topography). This requires a representation of the Earth’s surface as a generally curved surface that is embedded in three-dimensional Euclidian space. This book presents an analytical surface deformation theory to describe movement of the Earth’s crust with application to the velocities derived on the basis of GPS observations in the area of the Adriatic Sea and illustrates some local connections between deformations and stresses.