The "Metre Convention" in 1875 created the BIPM (the Bereau International des Poids et Measures, or in English, the International Bureau of Weights and Measures, which exists today to oversee the SI units). BIPM is in France. The MKS system was meters, kg, and second. BIPM exists under the authority of the General Conference on Weights and Measures (CGPM, Conference Generale des Poids et Mesures), which meets every 4 years to discuss the happenings of CIPM.
Also established from the Meter Convention was the CIPM (Committee for Weights and Measures), which consists of 18 individuals from different countries (this is starting to sound like the IETF structure).