The properties and wide application range of organic-inorganic hybrid (O-IH) sol-gel materials have attracted significant attention over the past decades. The combination of organic polymers and inorganic materials in a single-phase provides exceptional possibilities to tailor electrical, optical and mechanical properties concerning diverse applications. This unlimited design concept has led to the development of diverse coatings for several applications such as glasses, and metals to mitigate mechanical abrasion, erosion and corrosion. This class of materials could be easily obtained by sol-gel method at mild synthesis conditions. Furthermore, the large variety of available chemical precursors allows producing a diversity of coatings with tuned mechanical and thermal properties. This chapter will introduce the fundamentals of the sol-gel method to produce O-IH protective thin coatings and discuss the methodologies used to apply these materials onto different metallic substrates for erosion and corrosion protection.