Nanosphere lithography (NSL), originally termed ‘ natural lithography’ by its inventors,1 is becoming a widespread bottom-up technique to pattern solid surfaces at the sub-micrometer and nanoscales. Groups such as Van Duyne’s2 at Northwestern University and others3 undertook pioneering work on NSL in the 1990s and early this decade, and a growing number of research laboratories around the globe now use the technique in many scientific disciplines. The approach has applications in various materials systems, is fast and scalable to large surface areas, and is inexpensive in terms of equipment and operation. Some variants of the technique have reached a high level of maturity and control. Therefore, it is likely that it will soon be used in device fabrication.