Soyuz 30 carried Pyotr Klimuk and Mirosław Hermaszewski, the first (and to date, only) Polish cosmonaut, aloft.

The Soyuz docked with the space station on 29 June, and cosmonauts Klimuk and Hermaszewski were greeted by Vladimir Kovalyonok and Aleksandr Ivanchenkov, the resident crew who had been on board for 12 days.

One was crystallization experiments which produced 47 grams of cadmium tellurium mercury semiconductors for use by infra-red detectors on board the station.

[3] Hermaszewski participated in medical experiments which measured lung capacity and the heart during exercise and in a pressure suit.

[4] The Soyuz 30 crew packed their experiments into their capsule and returned to Earth 5 July, landing in a Rostov state farm field 300 km west of Tselinograd.