The complexity of System Earth requires an integrated observational strategy and infrastructure which has the potential to record diverse key diagnostic features. Accordingly, this infrastructure must include globally-distributed and technically varied instruments such as specialized Earth observation satellites, seismological instruments, magneto-telluric devices, observatories for the magnetic and gravity field, and analytical facilities. This challenge is met by the Modular Earth Science Infrastructure (MESI) at GFZ that integrates instrumentation and facilities supervised by external committees and is accessible for scientists from other research units and universities free of charge.