On January 13, 2017, the European Chemicals Agency (ECHA) sent the draft appendix on recommendations for nanomaterials applicable to the guidance on registration to the Forum, Member State Committee, and Risk Assessment Committee for consultation. The draft guidance outlines the minimum elements potential registrants need to consider when registering substances that fulfil the European Commission's (EC) Recommendation for the definition of nanomaterial. The aim of the draft guidance is to define the term "nanoform," the minimum criteria for distinguishing between different nanoforms, and the minimum set of elements that should be reported on the characterization of nanoforms. The draft guidance defines nanoform as a substance that meets the requirements of the EC's Recommendation for the definition of nanomaterial and has a shape and a surface chemistry. The three minimum elements to characterize nanoforms are: (1) size; (2) shape; and (3) surface chemistry. The draft guidance notes that these are the minimum elements necessary to characterize registered nanoforms in a registration dossier, and additional elements and/or additional refinement of these elements may need to be reported. The draft guidance includes a hypothetical example of the minimum elements that would be needed to report a nanoform.