This book presents a method for the prediction of mean flow data (i.e. skin friction, velocity profile and shape parameter) for adiabatic two-dimensional compressible turbulent boundary layers at zero pressure gradient. The transformed law of the wall, law of the lake, the van Driest model for the complete inner region and a correlation between the Reynolds number based on the boundary layer integral length scale and the Reynolds number based on the boundary layer momentum thickness were used to predict the mean flow quantities. The results for skin friction coefficient show good agreement with a number of existing theories including the van Driest II and the Huang et al. Comparison with a large number of experimental data suggests that at least for transonic and supersonic flows, the velocity profile as described by van Driest and Coles is Reynolds number dependent and should not be presumed universal. Extra information or perhaps a betler physical approach to the formulation of the mean structure of compressible turbulent boundary layers even in zero pressure gradient and adiabatic condition, is required in order to achieve complete (physical and mathematical) convergence wh en it is applied in any prediction methods.