Based on their rigid-rod structure all-conjugated, rod-rod block copolymers show a preferred tendency to self-assemble into low-curvature vesicular or lamellar nanostructures independent from their specific chemical structure and composition. This unique and attractive behaviour is clearly illustrated in a few examples of such all-conjugated block copolymers. The resulting nanostructured heteromaterials may find applications in electronic devices or artificial membranes.