The most impactful measures are catering and transport. Together they account for 60 to 70% of the CO2 footprint. For catering: local seasonal menus, plant-based food (up to 10 times lower than meat), minimal packaging. This raises awareness and can even save costs. For transport: group travel by bus or train cuts emissions dramatically. For materials: reusable cups and plates replace single-use products (saves money on repeat events). Third priority: venue choice based on green certification. Fourth: energy management (LED, natural light). These four points have the most impact. Live Impact advises on priorities by event type.