Twenty-five-thousanders (Russian: двадцатипятитысячники, dvadtsatipyatitysyachniki) was a collective name for the frontline workers from the major industrial cities of the Soviet Union who voluntarily left their urban homes for rural areas at the call of the All-Union Communist Party (Bolsheviks) to improve the performance of kolkhozes during the agricultural collectivisation in the Soviet Union in early 1930.
In November 1929, the plenum of the Central Committee of the Communist Party issued a decree on sending 25,000 workers with sufficient organizational and political experience to the rural areas to work in kolkhozy and in Machine and Tractor Stations (MTS).
The decree found a broad response among the workers of the country, but they often had to fight resistance from their factories, which needed them to fill production quotas.
The twenty-five-thousanders took part in establishing new kolkhozy and in strengthening the weak ones, conducting political, educational and cultural work among the inhabitants of the rural areas.
Mikhail Sholokhov wrote one of the most famous books on this subject: Virgin Soil Upturned (Russian: Поднятая целина, romanized: Podnyataya tselina, 1932 and 1960).