This book is the first to present the application of parabolic equation methods in electromagnetic wave propagation. These powerful numerical techniques have become the dominant tool for assessing clear-air and terrain effects on radiowave propagation and are growing increasingly popular for solving scattering problems. The book gives the mathematical background to parabolic equation modelling and describes simple parabolic equation algorithms before progressing to more advanced topics such as domain truncation, the treatment of impedance boundaries and the implementation of very fast hybrid methods combining ray-tracing and parabolic equation techniques. The last three chapters are devoted to scattering problems, with application to propagation in urban environments and to radar cross section computation. This book will prove useful to scientists and engineers who require accurate assessment of diffraction and ducting on radio and radar systems. Its self-contained approach should also make it particularly suitable for graduate students and other researchers interested in radiowave propagation scattering.