A side event was held at the twentieth meeting of the Convention on Biological Diversity's Subsidiary Body on Scientific, Technical and Technological Advice on 'other effective area-based conservation measures. On Monday 25 April, the WCPA Task Force on Other Effective Area-based Conservation Measures (OECMs) and the Secretariat of the CBD (SCBD) hosted a side event on OECMs. The event was chaired by Kathy MacKinnon (Chair, WCPA/Co-Chair, Task Force on OECMs) and was opened by Braulio Dias (Executive Secretary, SCBD) who underscored the importance of developing guidance on OECMs as a means of contributing to the security of biologically diverse areas that lie beyond the current protected area estate. Trevor Sandwith (Director, Global Protected Areas Programme, IUCN) suggested that the development of guidance on OECMs provides an important opportunity to consider the factors that lead certain areas that are currently not considered to be protected areas to support the conservation of biodiversity and to explore means of enhancing those qualities. Harry Jonas (Natural Justice/Co-Chair, Task Force on OECMs) presented an overview of the Task Force, the roadmap developed in Cambridge (January 2016) and the Task Force’s progress to date. David MacKinnon (Canadian Council on Ecological Areas - CCEA) presented on the CCEA’s work on OECMs, including a screening tool. Questions were raised by, among others, Puri Canals (Mediterranean Protected Areas Network), Simone Lovera (Global Forest Coalition) and Sarah Pearson Perret (Switzerland). Further information about SBSTTA-20 is available here.