We report the results of a study on aqueous solutions of hydrophobically modified polyelectrolytes (charge-neutral diblock copolymers) by different techniques which have been specifically chosen for demonstrating unambiguously the existence of micelles. Self-diffusion measurements by fluorescence recovery after photobleaching (FRAPP) and pulsed NMR spectroscopy measure the micellar sizes which are in agreement with light scattering data on dilute solutions. Cryo-transmission electron microscopy (Cryo-TEM) pictures confirm the existence of the micellar cores in contrast with homopolyelectrolyte solutions where no features are observed.