The average and local structure in the mixed-metal cyanides, Ni1/2Pt1/2(CN)2, Ni1/2Pd1/2(CN)2 and Pd1/2Pt1/2(CN)2 will be determined to give the M-C and M-N bond lengths, the ordering of CN groups and hence the preference of different metals for the carbon and nitrogen end of the CN ligand. Only total diffraction is capable of yielding this information as these materials are highly disordered. In addition to the crystal chemistry interest in these systems, the materials display NTE behaviour and attractive photophysics. These are a new type of photoluminescent material and this study forms part of our work on structure-property relationships in this field.