1910 - 1919
He participated in the work of two architectural studios before the First World War. One of them was in Warsaw and was first in joint ownership (with Derzhanovskim and Voitsekhovskii) and later into the domain Ai, on the street. Okulnik. The second, "Guy Sventitsky & Co», located in Minsk, in the house at the corner of Yukhnovich contemporary of Karl Marx and Engels. For a while he worked in Minsk and its surroundings, raised a lot of works of sacred and civil architecture. He participated in architectural competitions, where he received numerous distinctions and awards, including first prize in the competition for the design of the Bessarabian Market in Kiev; before that Guy had the experience of building a covered market in Warsaw. In 1914 he moved into Russia, the beginning of the First World War, met in Vladivostok. Where he organized a Polish colony and served as consul. In 1918 he left Russia. In 1919 he arrived in Minsk, but in the same year he left and returned to Warsaw. During the Polish-Soviet War was a member of the Polish Civil Guard. He held a lecture at the railway school. In the interwar period, he worked as an architect in the voivodship Pinsk.