Direct crystallization of polymer crystals along the long axis of carbon nanotubes (CNTs) to produce a hybrid nanostructured material is expected to retain the properties of CNTs and has the advantage of a strong polymer/CNT interface. Three different polymer systems are selected to elucidate the fundamental principles that govern the processing of organic–inorganic hybrid nanostructured materials with nanometer-scale architecture. The tunable character of the nanometer-scale hybrid architecture is investigated as a function of undercooling and polymer concentration. It is observed that while polyethylene and nylon 6,6 crystallize in a periodic manner as disk-shaped crystals along the long axis of the CNTs, the polypropylene–CNTs result in conventional spherulites. The reasons for these differences are analyzed.