Zygmunt Witalis Zaremba (1895, Piotrków, Poland – October 5, 1967, Sceaux near Paris, France), pseudonyms Andrzej Czarski (Czerski), Wit Smrek, was Polish socialist activist and publicist.
Zaremba was member of the Youth Association for Progress and Independence (Związek Młodzieży Postępowo-Niepodległościowej; 1911), Polish Socialist Party - Opposition (Polska Partia Socjalistyczna - Opozycja; 1912–1914), then member of the Polish Socialist Party (Polska Partia Socjalistyczna) and its Central Executive Committee (Centralny Komitet Wykonawczy; 1917–1918).
Since 1918 he stayed in Poland. Then, he was member of Polish Socialist Party authorities – Supreme Council (Rada Naczelna; 1919–1939) and Central Executive Committee (1921–1924, 1926–1939). During the years of 1921–1924 he was a vice-president of its Supreme Council.
In the years of 1922–1935 Zaremba was a deputy of a Sejm. During the Invasion of Poland (1939) he organised the Robotnicza Brygada Obrony Warszawy. Zaremba was a co-founder of conspiratory Polish Socialist Party - Freedom-Equality-Independence (PPS - Wolność-Równość-Niepodległość) and its administration member. In the years of 1944–1945 representative of the Council of National Unity (Rada Jedności Narodowej). In 1946 he moved to Paris, where he became a president of the Central Committee (Rada Centralna) of the Polish Socialist Party. In 1949 he co-founded Political Council (Rada Polityczna) in London. He was a president and co-founder of the International Socialist Office and then, until 1964, president of the Central-East Socialist Europe Union.
Zaremba was a co-author of Program Polski Ludowej (1941). He was an editor of party-press Robotnik, Pobudka, Związkowiec. Also an editor of Światło (1947–1959) and Droga (1959–1960).