Our international system of units (SI units) consists of 7 base units with the METRE for measurement of length, the KILOGRAM for mass, the SECOND for time, the AMPERE for electric current, the KELVIN for temperature, the CANDELA for luminous intensity, and the MOLE for amount of substance. A redefinition of the units KELVIN, MOLE, KILOGRAM and AMPERE is scheduled for 2018. Especially the replacement of the kilogram, which is at present represented by a prototype kept at the BIPM (Bureau International des Poids et Mesures), plays a crucial role in the discussion.

The presentation gives an overview about the evolution of our measurement system with a focus on a new kilogram and the importance of my Nobel Prize discovery (Nobel Prize in Physics 1985 for the quantum Hall effect) for the development of a new SI system.