The UN Convention to Combat Desertification (UNCCD) has made available an 'Impulse Report' and a 'Book of Abstracts' in advance of the UNCCD 3rd Scientific Conference, which will convene from 9-12 March 2015, in Cancún, Mexico. The Conference will take place as part of the 4th special session of the Committee on Science and Technology (CST S-4). The 3rd Scientific Conference is organized around three thematic sessions that correspond to three key challenges. The first session, on the diagnosis of constraints, will explore how to characterize and understand the vulnerability and adaptive capacities of ecosystems and populations in affected regions, including regions newly susceptible to the consequences of climate change. The second session, on responses, will discuss how to build on available knowledge, success stories and lessons learnt to promote implementation of better adapted, knowledge-based practices and technologies. The third session will address new monitoring and assessment methods available to evaluate the effectiveness of identified practices and technologies, as well as their scaling up. The Impulse Report, titled ‘Climate change and desertification: Anticipating, assessing & adapting to future change in drylands,' synthesizes current knowledge and raises questions in relation to each of these three major challenges to be addressed at the Conference. The report seeks to encourage an interdisciplinary and integrated approach by considering how land users, the policy and research communities, and other stakeholders can work together to better anticipate, assess and adapt to the combined effects of climate change and land degradation. It also considers the behavioral, governance and policy changes that may be needed to facilitate effective adaptation at the national and international levels.