The Pluronics^® (polyethyleneoxide-polypropyleneoxide-polyethyleneoxide, PEO-PPO-PEO) are the only amphiphilic block copolymers for which results for the kinetics of the copolymer exchange between micelles have been reported for several copolymers. The rate constants k⁺ and k^- for the copolymer entry/exit into/from micelles have been extracted from these results for 8 copolymers. Contrary to what is observed for conventional surfactants, k⁺ is smaller/much smaller than for a diffusion-controlled process. Both k⁺ and k^- decrease significantly with increasing number of PO units, n_PO, but vary relatively little with the number of EO units, n_EO, in the copolymer. The plot of log k^- vs t^4/3n_PO^2/3 (t is a factor correcting for temperature) is linear. This behavior suggests that the PO block is somewhat folded in the free (unimer) state, with less contact with water than in the fully extended conformation. This behavior explains why, for other amphiphilic block copolymers, the reported values of k^- show remarkably little dependence on the copolymer architecture. An extrapolation of the Pluronics^® results on the basis of Aniansson's expression for k^- suggests that for copolymers with a more hydrophobic block (i.e., polybutyleneoxide or polystyrene) the exchange process may be too slow for being detected on the laboratory time scale. The folding of the hydrophobic block in the unimer state precludes the determination of the free energy increment for the transfer of a hydrophobic unit from water to micelle from the cmc dependence on the hydrophobic block polymerization degree. The micelle formation/breakdown of Pluronics^® micelles appears to occur via fragmentation/coagulation reactions.