This is the first book devoted especially to the problem of light scattering and absorption by inhomogeneous and anisotropic spherical particles. Unlike other books in the field, considerable attention has been given to various aspects of light absorption inside particles, including internal field distributions, MDR resonances, absorption in restricted regions inside particles. It contains many results (more than 100 figures) computed for polydisperse particle systems and algorithms and provides the possibility to use them (web site). Although main emphasis is given to optical properties of atmospheric aerosol, the book also deals with many other practical applications involving inhomogeneous and anisotropic particles.