This video shows how a pulsed nanosecond laser beam can be used for the modification of a surface with structures on the micron scale in a single shot on an area of mm2. As a start interference is explained with examples of water waves and light. For the light a laser beam is split into two beams which are recombined on the surface to be patterned. The structures are detected by diffraction from the formed surface pattern. Atomic force microscopy is used to image the surface. This technique can be used for the structuring of single molecule layers, catalysts, surfaces of metals, semiconductors and polymers.