In November 2018, Parties to the Convention on Biological Diversity adopted at the 14th Conference of the Parties a definition of an “other effective area-based conservation measure” (OECM) as well as guiding principles, common characteristics and criteria for identification of OECMs (CBD/COP/DEC/14/8). OECMs may be managed for many different objectives but they must deliver effective conservation. They may be managed with conservation as a primary or secondary objective or long-term conservation may simply be the ancillary result of management activities. OECMs can contribute to ecologically representative and well-connected conservation systems, integrated within wider landscapes and seascapes, and in doing so, generate a range of positive conservation outcomes. The WCPA Task Force on OECMs has produced these guidelines to assist Parties in interpreting and operationalising Decision 14/8 and to start to develop a body of good practice around recognising and reporting OECMs. It is designed for application at various scales, ranging from understanding whether an individual area is an OECM to reporting OECM statistics at the national and global level as a means to assess progress on achieving conservation targets.