Somni Solutions, a small Dutch fiber optic sensing company has been successfully delivering sensors for different modules of ITER. Somni started with he delivery of fiber optic temperature sensors and accelerometers for the ITER Neutral Beamline and has now won a tender to deliver fiber optic accelerometers which are to be installed inside the ITER Portplugs. These Portplugs are the diagnostics windows through which the plasma of the Tokamak is visible and is diagnosed. Vacuum conditions, extreme radiation levels, high temperatures, a 4 Tesla varying magnetic field … these conditions are among the most difficult environmental conditions for which Somni has developed sensors. We will share more insight in the ITER Tokamak, specifically the location and purpose of the Portplugs. Discuss the need for accelerometers inside the Portplugs and tell the story on what design challenges Somni faced when developing these special sensors.