Atomic Physics is certainly the oldest field in which Quantum Mechanics has been used and has provided the most significant proofs of this new theory. Most of the basic concepts, except those more recently developed in field quantization, have been understood for quite a time. Atomic Physics began to serve as a basis for other fields such as molecu lar, solid state or nuclear physics. A renewal of interest in Atomic Physics began in the sixties, after the discovery of Quantum Electro dynamics, and later when it provided some basic tests of fundamental questions like parity violation, time...