The transport sector is currently facing a complete overhaul due to ever increasing restrictions on greenhouse gas emissions. As described in the European Green Deal, the main goal is to achieve net zero emissions by 2050 and to limit global warming to 1.5–2ºC above pre–industrial levels. Owing to their low density, magnesium alloys could become a turning point in light vehicle design and therefore, drastically reduce the energy consumption and gas emissions in this sector. At present, the most promising strategies to increase the range of applications of magnesium alloys are concerned with the development of new alloys and protection systems with higher corrosion resistance.Commercial protection mechanisms for magnesium alloys are often based on the use of Cr(VI) compounds, which is known to be toxic and carcinogenic. Therefore, the development of Cr(VI)–free surface treatments has become one of the main research lines in recent years. The alternatives should also provide active corrosion protection and be environmentally friendly.The Introduction in this Thesis provides an overview of magnesium alloys and their corrosion behaviour as well as a literature review on protection strategies, including trends on smart surface engineering approaches which have been postulated as potential replacements for Cr(VI)–based treatments...