Layered metal nanoparticle structures have been shown to have application across a broad range of fields, notably as a specific and sensitive imprinting matrix for sensing targets, as a substrate for electrochemical reactions, and as a surface with which to control the uptake and release of molecules. On page 51 I. Willner and co‐workers review how the synthesis of layered nanoparticles on an electrode provides a means of both recording sensitive responses to changes within the layers and inducing changes through electrochemical triggering.