A systematic study of iron-aluminum alloys has shown that Fe-16 at. % Al alloys are not very sensitive to environmental embrittlement. The Fe-22 and -28 at. % Al alloys are sensitive to environmental embrittlement, and the effect can be reduced by the addition of chromium and through the control of grain size by additions of zirconium and carbon. The Fe-16 at. % Al binary, and alloys based on it, yielded over 20% room-temperature (RT) elongation even after high-temperature annealing treatments at 1100°C. The best values for the Fe-22 and -28 at. % Al-base alloys after similar annealing treatments were 5 and 10%, respectively. A multi-component alloy, FAP, based on Fe-16 at. % Al was designed, which gave an RT ductility of over 25%.