Metathesis reactions of dinuclear halo-bridged complexes of the late transition metals were studied by NMR. For selected combinations of 15 different complexes, asym. complexes are formed in a dynamic equil. The equil. consts. were calcd. and the trends therein are discussed. A theor. anal. of halo-bridged complexes contg. (C3H5)MX, (H3P)MX2, [(H3P)2MX]+, and (ppy)2RhCl fragments (M = Pd, Pt; X = Cl, Br, I; ppy = anion of 2-phenylpyridine) was carried out to gain further insight into (i) the influence of the bridging halogen atoms on the equil., (ii) the electron transfer, (iii) the thermodn. stability and the dynamic equil. behavior, and (iv) structural differences between sym. and asym. halo-bridged complexes.