We here examine the processes of scattering in the Earth, the various zones where it is important and the way that these different zones influence observed seismograms.Guided waves in heterogeneous structures play an important role at high frequencies, and can be described as a stochastic waveguide effect. Waves can be guided even within high wavespeed zones by elongate heterogeneity. We discuss examples from the propagation of deep earthquakes in subduction zone environments, and for the oceanic and continental lithosphere.