The book presents a new method of asymptotic analysis of boundary layer problems, the Successive Complementary Expansion Method (SCEM). The first part is devoted to a general presentation of the tools of asymptotic analysis. This part gives also the keys to understand a boundary layer problem and of the methods to construct an approximation.
The second part is devoted to SCEM and its applications in fluid mechanics. The advantages of SCEM are discussed in comparison with the standard method of matched asymptotic expansions.