The class of quasiseparable matrices includes several other well-known matrices, such as band matrices, diagonal plus semiseparable matrices, tridiagonal matrices, and unitary Hessenberg matrices; and arises naturally in classical control theory. As with any matrix operator, computational benefits can be obtained from factoring, especially by utilizing unitary factors. This book provides some detail concerning a current (largely unitary) approach to factoring quasiseparable matrices described by Y. Eidelman and I. Gohberg (2002), derived in part from a previous description by P. M. Dewilde...