Molar enthalpies of mixing Delta(mix)H(m)(0), of the LiBr-NdBr3, NaBr-NdBr3, KBr-NdBr3, RbBr-NdBr3, and CsBr-NdBr3 liquid binary systems have been measured with a Calvet-type high-temperature microcalorimeter under argon at 1063 K over the whole composition range. Mixing of the two liquid components was carried out using a break-off ampoule technique. For all the systems, the enthalpies of mixing were negative and their minima (at x(NdBrs)approximate to 0.4) were -0.7, -5.4, -12.4, -17.8 and -20.1 kJ mol(-1), respectively. The results have been compared with data previously published for MCl-NdCl3 systems and discussed in terms of possible complex formation.