Interactions between micelles and tripositive ions of metal complexes such as [M(en)(3)](3+) (M = Co or Cr, en = ethylenediamine), [M(chxn)(3)](3+) (chxn = (R,R)-1,2-cyclohexanediamine), and [M(phen)(3)](3+) (phen = 1,10-phenanthroline), were studied using Co-59 NMR spectroscopies and paramagnetic Cr(III)-induced C-13 NMR relaxations of the surfactants. The magnitudes of the changes in Co-59 chemical shifts and relaxation rates for [Co(en)(3)](3+) (= en complex) and [Co(chxn)(3)](3+) (= chxn complex) were dependent on the type of the head group : The carboxylate and alaninate surfactants caused larger changes in the Co-59 NMR parameters than the sulfonate and sulfate ones did. The Co-59 longitudinal and transverse relaxation rates were measured for the typical systems; these results gave effective Co-59 electric field gradients (efgs) and effective correlation times for the three complex ions in the micellar solutions. The effective Co-59 efgs obtained for the en and chxn complexes were larger in the carboxylate micelles than in the sulfonate and sulfate micelles. This result is in accord with the larger changes in the Co-59 chemical shifts. The paramagnetic Cr(III)-induced C-13 relaxation studies for each carbon of the surfactants suggest that [Cr(chxn)(3)](3+) is located at the micelle-water interface as well as the en complex. The correlation times and their activation energies also gave useful information on the selective interactions of the metal complex ions in the micellar solutions.