Preliminary studies of the flow model in the wall layers of the turbulent boundary layer are presented. Results are summarized for investigations of positive pressure gradients, zero and negative pressure gradients, readjusting zones, and the later stages of transition. In all cases, the special visual methods developed for these studies show a definite three-dimensional vortex-flow model. The presently available details of this model are described, a possible interpretation of the physics of the turbulent boundary layer is given, and some of the many implications of the flow model are discussed.