A series of substituted hexarhodium carbonyl clusters [Rh6(CO)15L] (L = PR3 (R = alkyl, aryl), P(OPh)3, NCMe, I-) has been studied by variable temperature and two-dimensional, X-{103Rh}, (X = 13C, 31P) HMQC and 13C EXSY NMR spectroscopy in solution. At low temperatures, the spectra are consistent with retention of the solid state structure. Different localised exchanges of terminal (COt) and face-bridging (COfb) CO's are found to occur over different atoms of the Rh6-octahedron at higher temperatures and the different pathways of the exchanges are discussed. When L = PR3 (R = alkyl, aryl), the lowest energy scrambling surprisingly involves exchange of COt and COfb, associated with the substituted rhodium (S-type), with concomitant exchange of L between the two terminal sites on the substituted rhodium, followed by other localised stereosp