In this monograph we describe an important and relatively new class of phenomena in the field of high-resolution atomic spectroscopy: the interference effects manifest in the angular distribution and polarization of spontaneous radiation and absorption by atoms. Although the quantum-theoretical descrip- tion of these interference effects is quite subtle, it turns out - as so often in quantum mechanics - that a simple classical or semi-classical description offers much insight and can even explain quantitative features. In this presentation, however, we attempt to give the full story....