Polystyrene-block-poly(4-vinylpyridine) with nominally one pentadecylphenol molecule hydrogen-bonded to each pyridine group has been electrospun, leading to fibers with a hierarchical, structure-within-structure morphology (see Figure). An internal structure on the nanometer length scale exists within a structure on the tens-of-manometers length scale. Internal porosity can be obtained by selective removal of the amphiphile.