 Making effective policy often means balancing highly interacting but diverse objectives. Striking the right balance can unlock synergies that promote progress on multiple goals. Failing to do so can restrict progress and see momentum lost. The 2030 Agenda and the Sustainable Development Goals is designed as an integrated and indivisible framework. Since progress on one target can affect other SDGs positively or negatively, the goals and targets cannot be treated as isolated entities, but their interactions must inform implementation strategies. The international policy community have recognised this need for systemic approaches to SDG implementation. SEI has responded to this challenge by developing the SDG Synergies Tool. It helps to record, visualise and analyse how multiple targets interact as a system in a given context. SDG Synergies is a practical tool for understanding how goals and targets interact using systems thinking. SDG Synergies was originally designed to support governments in implementing the 2030 Agenda. It can also be customised to include other agendas or policy areas. The tool facilitates a structured participatory process in which stakeholders discuss and assess how the goals interact in the given context. Their assessments are entered into a cross-impact matrix, which forms the basis for subsequent analysis. In the tool, there are multiple options to analyse and view the system, including from the perspective of a selected goal. The options are developed in particular to inform prioritisation of goals to maximise progress on the agenda as a whole. There are options that can guide cross-sectoral collaboration. Network analysis techniques are embedded in the tool to provide these insights. The SDG Synergies Tool is interactive and easy to use. Intuitive analysis and visualisations facilitate dialogue and learning between participants and provide an overview of how policy objectives, such as the SDGs, interact as a system. The tool can be used for global, national or subnational studies, supporting policy-making processes at any level. For more information, please visit www.sdgsynergies.org or www.sei.org and download the guiding manual.