Synergies and trade-offs between sustainable development goals and targets: innovative approaches and new perspectives

The sustainable development goals (SDGs) were adopted by the United Nations on 25th September 2015 and are now mid-way to the target implementation deadline of 2030. A set of 17 goals with 169 targets are being used to guide all UN Member States in implementing the challenging 2030 Agenda for Sustainable Development. From the beginning, it was recognised that the goals and targets were interlinked and integrated (UN 2015) and that this had to be considered for SDG implementation to ensure policy coherence. However, while addressing this agenda, countries may lose sight of the synergies and trade-offs between goals and their targets. Reasons for this are linked to the complexity of monitoring a large number of indicators (232), the lack of methods, data, and/or means to quantify some of the indicators, the lack of a definitive framework to address synergies and trade-offs, and gaps in our knowledge on how goals and targets influence each other. Yet, understanding how these interactions take place remains essential to minimise trade-offs and maximise synergies, and in the process, ensure we are making progress towards achieving the SDGs and avoid wasting resources when doing so. The issue is, therefore, complex, and in the past few years approaches have been developed to identify and quantify synergies and trade-offs between goals and between targets, particularly at the national scale at which countries report to. Less work is underway on synergies and trade-offs at the global or sub-national scales, even though these scales are also relevant to ensure equitable development (‘leaving no one behind’ as prioritised by the UN-CEB 2017) internationally, nationally, and within countries (Nilsson et al. 2016a).