Assembly of catalyst-functionalized amphiphilic block copolymers into polymer micelles and vesicles. Characteristics of a nanoreactor system are shown using the polymer micelles including (a) the catalysts are protected and isolated from each other by the micellar shell, (b) substrates are effectively sequestered by the core from the surrounding environment, creating a highly concentrated environment for confined catalysis, (c) the nanostructure shell may regulate the access of substrates to the catalyst-containing micelle core. Reprinted with permission from reference .