Light Scattering by Systems of Particles comprehensively develops the theory of the null-field method, while covering almost all aspects and current applications. The "Null-field Method with Discrete Sources" is an extension of the Null-field Method (also called T-Matrix Method) to compute light scattering by arbitrarily shaped dielectric particles. This book incorporates FORTRAN programs and exemplary simulation results that demonstrate all aspects of the latest developments of the method. Worked examples of the application of the FORTRAN programs show readers how to adapt or modify the programs for their specific application.