This is both promo text and back cover copy. This volume combines the discussions of two workshops: one devoted to wavelets, multigrid and other fast algorithms (multipole, FFT) and their use in wave propagation, and another devoted to waves in random and other complex media. The majority of the chapters deal with the effects of inhomogeneities of wave propagation both theoretically and computationally. They include topics such as waves in random media, coherent effects in scattering for random systems with discrete spectrum, interaction of microwaves with sea ice, scattering in magnetic field, surface waves, seismogram envelopes, backscattering, polarization mode dispersions, and spatio-temporal distribution of seismic power. Several chapters describe numerical methods, such as fast algorithms for solving electromagnetic scattering problems, and the panel clustering methods in 3-d BEM.