The isolation of graphene and subsequent studies showed that obtaining atomically thin crystalline sheets was feasible and possessed extraordinary properties.This result opened the door to an entirely new family of materials known as two-dimensional or 2D materials.Research in this field is intense:the emergence of new 2D materials,the properties of their combinations and the ability of graphene to reinvent itself,showing novel and exciting properties,make it likely that this field will continue to be one of the leading topics of materials science and condensed matter physics.In less than two decades,there have been tremendous advances in the fundamental understanding,materials preparation,characterization,processing and accurate design of layer-by-layer assemblies of 2D materials.Graphene and many other related 2D materials have established themselves as a very productive scientific field with a high potential for technological applications,some of them already on the market.This special issue has been designed to collect a good number of high-quality articles[1-7],including both reviews and cutting edge research,summarizing a current view of the field and its future directions.