In this volume, six review articles which cover a broad range of topics of
current interest in modern optics are included.
The first article by S. Saltiel, A.A. Sukhorukov and Y.S. Kivshar presents an
overview of various types of parametric interactions in nonlinear optics which
are associated with simultaneous phase-matching of several optical processes in
quadratic non-linear media, the so-called multi-step parametric interactions.
The second article by H.E. Tureci, H.G.L. Schwefel, Ph. Jacquod and A.D. Stone
reviews the progress that has been made in recent years in the understanding of
modes in wave-chaotic systems.
The next article by C.P. Search and P. Meystre reviews some