An apparatus and a method for producing nanostructured surfaces are particularly suited for producing surfaces having very low roughness over large lateral extents. The method includes the following steps: providing an article having a surface to be structured; generating short-pulse laser radiation with laser pulses whose pulse durations lie in the subnanosecond range, preferably in the range of 100 fs to 300 fs, directing the short-pulse laser radiation onto the surface to be structured on the article, such that a fluence F of each individual pulse of the short-pulse laser radiation is less than a multishot threshold fluence Fth for a multishot laser ablation, but the fluence F is chosen to be high enough that defects can be produced by way of nonlinear interactions. Preferably, a fluence F in the range of 65% to 95% of the multishot threshold fluence Fth for a multishot laser ablation is used.