International socio-environmental spillover effects on achieving the national SDGs

In an increasingly interconnected world, one country’s ability to achieve the United Nations Sustainable Development Goals (SDGs) is affected by positive or negative spillovers from other countries. Yet, little research has considered these spillovers in monitoring SDG progress. Ignoring these effects may result in achieving one country’s SDGs at the cost of the other or miss positive synergies. At the country level, 91% of the countries (accounting for 94% world population) improved their SDG Index through international interactions. Despite the overall benefit, we found that, among the 17 SDGs, 15 benefited from international interactions while two were negatively impacted, and both deal with the dimension of social fairness. Besides, we found higher-income countries generally benefited more, while lower-income countries benefited less and occasionally disadvantaged from the spillover impacts. Further analysis found that the negative spillovers were dominantly generated by a few powerful and developed countries, such as the United States, Germany, Japan, Italy, and China, while the impacted countries are mostly less-developed. Furthermore, we found the spillover impacts more frequently occurred between faraway countries with unequal economic levels, which indicates distant interactions lead to more socio-environmental inequality among countries in terms of achieving SDGs. The study provides a quantitative understanding of the often-ignored spillover effects on achieving sustainability, therefore, inform (inter)governmental agencies to target the negative spillovers and empower disadvantaged countries to better achieve SDGs globally.