In a recent review of the published literature on this system it was concluded that there is a lack of experimental data in this system particularly in regions of the system with less than 75 atomic per cent of each one of the components (1). In order to provide some consistent data over a substantial range of composition an experimental determination of the phase equilibria at 1173K and from 0–50 atomic % Al is being carried out. The main experimental technique being used is quantitative electron microprobe analysis (JEOL 733) by wavelength dispersive x-ray spectrometry. In addition, x-ray diffraction is being used to establish the structures of phases present and optical metallography of cast structures to determine the fields of primary crystallization. In addition to establishing the phase equilibria at this temperature the composition range for the existence of the AlNi2Ti phase is being determined. The results thus far are compared with previous experimental data and calculated isothermal sections (2).