Derek P. Tittensor, Matt Walpole, Samantha L. L. Hill, Daniel G. Boyce, Gregory L. Britten, Neil D. Burgess, Stuart H. M. Butchart, Paul W. Leadley, Eugenie C. Regan, Rob Alkemade, Roswitha Baumung, Céline Bellard, Lex Bouwman, Nadine J. Bowles-Newark, Anna M. Chenery, William W. L. Cheung, Villy Christensen, H. David Cooper, Annabel R. Crowther, Matthew J. R. Dixon, Alessandro Galli, Valérie Gaveau, Richard D. Gregory, Nicolas L. Gutierrez, Tim L. Hirsch, Robert Höft, Stephanie R. Januchowski-Hartley, Marion Karmann, Cornelia B. Krug, Fiona J. Leverington, Jonathan Loh, Rik Kutsch Lojenga, Kelly Malsch, Alexandra Marques, David H. W. Morgan, Peter J. Mumby, Tim Newbold, Kieran Noonan-Mooney, Shyama N. Pagad, Bradley C. Parks, Henrique M. Pereira, Tim Robertson, Carlo Rondinini, Luca Santini, Jörn P. W. Scharlemann, Stefan Schindler, U. Rashid Sumaila, Louise S.L. Teh, Jennifer van Kolck, Piero Visconti, Yimin Ye

In 2010, the international community, under the auspices of the Convention on Biological Diversity, agreed on 20 biodiversity-related "Aichi Targets" to be achieved within a decade. We provide a comprehensive mid-term assessment of progress toward these global targets using 55 indicator data sets. We projected indicator trends to 2020 using an adaptive statistical framework that incorporated the specific properties of individual time series. On current trajectories, results suggest that despite accelerating policy and management responses to the biodiversity crisis, the impacts of these efforts are unlikely to be reflected in improved trends in the state of biodiversity by 2020. We highlight areas of societal endeavor requiring additional efforts to achieve the Aichi Targets, and provide a baseline against which to assess future progress.