A method and apparatus for transforming vertically-aligned nanostructures into densified, horizontally-aligned arrays. A contact element such as a roller is used to topple an array of carbon nanotubes or other nanostructures by drawing or rolling the contact element across the surface of the substrate such that the vertically-aligned nanostructures are forced into at least partial horizontal-alignment while being densified to give the transformed array enhanced properties. The contact element engages the nanostructures at a location below their upper distal end to topple and densify the array without disrupting the relative alignment of the individual nanostructures in the array. Transfer printing of the nanostructures is also provided.