Components often require high strength, high hardness, or high wear resistance to meet the demands of high performance applications. To meet these requirements, a martensitic microstructure is required. In powder metallurgy (PM), the martensitic structure can be achieved through conventional heat treatment or through sinter hardening. PM offers unique alloying techniques which can be used to develop the desired microstructure. Even if the resulting microstructure is predominantly martensitic, differences in final performance are often observed. In this paper, common alloying systems are compared in the martensitic condition. The microstructure and resulting properties of the different alloys are compared and discussed.