The Moscow-based Group for the Study of Reactive Motion (also known as the Group for the Investigation of Reactive Engines and Reactive Flight or Jet Propulsion Study Group; Russian: Группа изучения реактивного движения, Gruppa izucheniya reaktivnogo dvizheniya), abbreviated as GIRD (ГИРД), was a Soviet research bureau founded in 1931 to study various aspects of rocketry. GIRD launched the first Soviet liquid propellant rocket in August 1933. In November 1933 it was incorporated into the Reactive Scientific Research Institute (Реактивный научно-исследовательский институт, Reaktivnyy nauchno-issledovatel’skiy institut, РНИИ, RNII).

The inspiration for establishing the organisation came from Fredrich Tsander, a scientist, inventor, and romantic who dreamed of space travel. Tsander had begun to consider rocket-powered interplanetary flight as early as 1907 and was one of the founding members of the Society for the Study of Interplanetary Communication in 1924. In September 1931 Tsander formed the Moscow-based 'Group for the Study of Reactive Motion', better known by its Russian acronym “GIRD”. Initial funding was provided by Osoaviakhim however it was insufficient to cover production costs. In April 1932 Tsander began working full time for GIRD, however most other personnel worked at night or in their spare time. The personnel jokingly referred to GIRD as “Gruppa inzhenerov, rabotayushchaya darom” (group of engineers working for nothing).

Local GIRDs also developed in other cities, particularly Leningrad, but also in Kharkiv, Baku, Tiflis, Arkhangelsk, Novocherkassk and Bryansk.

A key contributor to GIRD came from a young aircraft engineer Sergey Korolev, who would later become the de facto head of the Soviet space programme. In 1930 while working as a lead engineer on the Tupolev TB-3 heavy bomber he became interested in the possibilities of liquid-fueled rocket engines to propel airplanes. This led to contact with Tsander, and sparked his interest in space exploration and rocketry.

In May 1932, Sergey Korolev replaced the ailing Tsander as the head of GIRD. At this time the group was organized as four brigades to further optimise their efforts, as follows:

Under Korolev's leadership GIRD began to attract additional funding from the Red Army's Directorate of Military Inventions, which enabled GIRD to obtain better equipment and pay personnel, which by 1933 totaled approximately 60 personnel.

Tsander died unexpectedly from an illness on March 28, 1933, and his engineer, Leonid Konstantinovich Korneev, became the new leader of his Brigade. An exact copy of the GIRD-X can be found on Tsander's headstone in Kislovodsk.

Tsander had begun work on the OR-1 experimental engine in 1929 while working at the Central Institute for Aircraft Motor Construction; this subsequently became GIRD Project 01. It ran on compressed air and gasoline and Tsander used it to investigate high-energy fuels including powdered metals mixed with gasoline. The chamber was cooled regeneratively by air entering at the nozzle end and also by water circulating through a coil.