Scientific and technological interest in one-dimensional nanomaterials, in particular carbon nanotubes(1,2), is a result of their fascinating properties and their ability to serve as templates for directed assembly. For applications in nanoelectronics it is necessary to create ordered arrays of nanotubes for large-scale integrated circuits, an area in which there has been significant progress(3-7), and to produce controllable patterns on individual nanotubes so that multiple transistors can be fabricated on them, an area where progress has been slower(8-14). Here, we show that judiciously selected crystalline block copolymers can be periodically decorated along carbon nanotubes, leading to amphiphilic, alternating patterns with a period of similar to 12 nm. In addition, end-functionalization of the block copolymers allowed gold nanoparticles to be periodically attached to the nanotubes. This approach provides a facile technique for the periodic patterning of one-dimensional nanomaterials.