AbstractGrowth phenomena and magnetism of metallic films are not easy to describe at the same level of precision. A small variation of distances can drastically modify the magnetic properties of thin metallic films. In this contribution different aspects encountered in the growth of thin magnetic metallic films are addressed. Within an itinerant magnetism scheme, the main difficulty arises from the number of possible magnetic arrangements induced by the competition between nearest-neighbors Ferromagnetic and Antiferromagnetic couplings. However we show that the description of the electronic and magnetic structure at T = 0 K by well-established band structure frameworks provides useful and precise information on the growth of a transition metal on another. Due to the large amount of experimental data available, the Fe/Cr system is taken as an example. The influence of steps at the interface is discussed and the possibility of magnetic domains is shown. A simple model of growth taking into account variable interdiffusion rate and layer-by-layer quality is given. These simulations are used to explain experimental results where interdiffusion at the interface is very common.