On September 16, 2014, the Organization for Economic Cooperation and Development (OECD) published a document entitled Report of the Questionnaire on Regulatory Regimes for Manufactured Nanomaterials 2010-2011. The Report summarizes responses to the Working Party on Manufactured Nanomaterials (WPMN) Questionnaire on Regulated Nanomaterials: 2010-2011, which was issued July 12, 2012. The Questionnaire contained four sections related to the oversight of nanomaterials in various OECD jurisdictions: regulatory updates; definitions and/or legal approaches for nanomaterials by jurisdiction; regulatory challenges; and opportunities for collaboration. Australia, Canada, Denmark, the European Union, France, Germany, Italy, Netherlands, and the U.S. submitted fourteen responses for legislation covering chemical substances and/or products, including industrial chemicals, therapeutics, foods and drugs, and biocides, as well as occupational health and safety, consumer products, packaging, and labeling. Respondents agreed on using existing regulatory frameworks to regulate nanomaterials, although some jurisdictions, such as France, have developed reporting regimes specific to nanomaterials to gather information on uses and quantities. According to the responses, developing regulatory definitions “still seems to be a fairly challenging issue for regulatory bodies; however, regulatory definitions have been developed and now are being used by some jurisdictions.” The definitions tend to consider a 1-100 nanometer (nm) size range, unique properties when outside of 1-100 nm, both internal and external structure, and have addressed ways to differentiate between materials that are engineered nanomaterials and traditional chemicals that have nanoscale components by using percentage cut-offs.