Bio#medical and #health #informatics (BMHI) has traditionally focused on human-centric clinical data to support individual #patient care and #health systems. However, contemporary #health challenges driven by climate change, biodiversity loss, and ecological degradation demand an expanded paradigm that addresses interdependencies among human, animal, and environmental #health. This editorial introduces a new JMIR #medical #informatics section on “Planetary #health #informatics” (PHI), an essential evolution extending #informatics praxis beyond human #healthcare toward Earth’s interconnected systems. JMIR #medical #informatics is launching a call for papers for a new section dedicated to advancing PHI theory, methods, and applications for a sustainable future shaped by human impact on Earth. We invite authors to submit work that explores how PHI integrates species, ecosystem, and geophysical data to address critical global challenges, including metagenomic disease surveillance, climate-related hazard forecasting, environmental pollution monitoring, and #health infrastructure decarbonization. By synthesizing broader ecological frameworks, we present a roadmap for transforming fragmented data streams into planetary-scale intelligence.