History of Science and Engineering Annotation << Back Italian Scientist Giovanni Giorgi and his Contribution to the Creation of the International System of Units Trunov G.M. The birth of the International System of Units (the SI) is inseparably linked to the personality of Italian scientist Giovanni Giorgi. The article shows how the idea of Georgie, he proposed in 1901, had led to the creation in 1935 of the four-dimensional Georgi system, which became the basis for the future SI. By the early twentieth century in the field of electromagnetism for research and practice there are two systems of units: the three-dimensional CGS system (based units are centimeter, gram, second), and the absolute practical system of electromagnetic units (ohm, volt, ampere, etc.). In 1901 Giorgi showed that the «absolute» system of practical units could be combined with the three mechanical units metre, kilogram and second to constitute a single coherent four-dimensional system of units. Four units – metre, kilogram, second and, for instance, ohm or ampere – could be chosen as base units from which all other practical electrical units could be derived. The units of such four-dimensional system («the Georgi system») became in the future units of the International System of Units (the SI). Keywords: Giovanni Giorgi; the International System of Units (SI); the CGS system; the practical system of electromagnetic units; metre; kilogram; second; ampere. Contacts: E-mail: plazma@perm.ru Pp. 03-14.