Over the years, it became more and more evident that governmental considerations on new materials should not be limited to the ‘simple’ nanomaterials. Furthermore, many of these (nano) materials possess/display an additional complexity, e.g. a new or enhanced functionality and/or multiple components. This may lead to further challenges compared to ‘simple’ nanomaterials They are part of a broader material category known as "advanced materials." The term "advanced materials" (AdMa) is used broadly and in various contexts. Therefore, the OECD has chosen to concentrate on the connections between nanotechnologies and AdMa, aiming to establish a common understanding of the term's scope for OECD usage. Through a questionnaire and a review of previous initiatives in this field, the OECD gathered Delegations' perspectives. The questionnaire results led to the creation of a Working Description on Advanced Materials (WD AdMa), intended to outline a framework for future work.