Nutrient budgets are tools that help us track how nitrogen and phosphorus move through the environment. These nutrients are essential for growing food, but when too much ends up in rivers, lakes, or the atmosphere, they can cause serious problems like water pollution or climate-warming emissions. Today, nutrient budgets are used to guide decisions in farming, environmental protection, and public policy. But many current approaches fall short. In this talk, we draw on insights from an international team of scientists and decision-makers to highlight 25 common challenges, from missing data and outdated assumptions to the difficulty of applying national-scale tools to local issues. We’ll also show how new pressures like changes in diets, more extreme weather, and changes in waste management, are making traditional methods for creating nutrient budgets less effective. To keep these tools useful, we need to rethink how they’re designed and communicated so that they’re clear, accurate, and actually helpful for managing the land, water, and climate systems we depend on.