Alloys based on the intermetallic compound orthorhombic titanium aluminide have the potential to replace steels, nickel and titanium alloys for some aero-engine component applications. The introduction of orthorhombic alloys could result in reduced weight and higher operating temperatures for engines. This in turn would lead to higher thrust-to-weight ratios and greater fuel efficiency. The Brite-Euram-funded programme EPROTAC is developing processing routes for orthorhombic alloy components with properties which are superior to current alloys.