Two-dimensional systems have recently emerged as very promising candidates for future electronic devices. An ordered 2D array of nanocrystals can be created by letting nanocrystals self-assemble and connect at a liquid surface. This new structure shows excellent long range order on both the nanocrystal and atomic level. Experiments at beamline ID10 revealed how the nanocrystals order themselves and ‘click together’ to produce beautiful 2D superlattices.