The next generation of computational devices will require novel materials to meet the technological demands of data processing and storage. Spintronics is concerned with utilising the electron spin degree of freedom, in addition to electron charge, for the development of smaller components and increased data-processing speed whilst also decreasing overall power consumption. The phenomenon of half-metallicity arises in some magnetic materials where the material is conducting for one electron spin direction, either up or down, whilst semiconducting or insulating in the other. This concept was first introduced in 1983 and the spin control properties of these materials play a crucial role in the field of spintronics. In spite of this long history, most existing half-metals do not meet the needs of functional spintronics devices, therefore better half-metallic candidates need to be developed.