This volume consists of seven chapters from leading experts in the field. The first topic to be presented is on the propagation of weak discontinuities with applications to fluid mechanics. Solutions and anomalies of the boundary layer equations for axial flow along a circular cylinder are described. Wall pressure fluctuations under turbulent boundary layers are discussed in some details. The mass transport induced by water waves are described in context of boundary layers. A theoretical study of laminar convection flow over a semi-infinite vertical plate is presented and some discussion of the convection layer is made.