In 1961, upon his graduation, he began working at the Scientific Research Institute of Broadcasting Reception and Acoustics [2] in (Leningrad).

It was then that he left his scientific career, and in 1965 the All-Union State Institute of Cinematography (VGIK).

Those colleagues included Pavel Kogan,[9] Mikhail Litvyakov,[10] Semyon Aranovich, Valery Guryanov.

He was a member of the jury of international Film Festivals in Nyon (Switzerland, 1992), Leipzig (2002), Kraków (2003), Saint Petersburg (2003), Warsaw (2007), Plovdiv (2007).

Since 1993, Mostovoy has been living and working as a freelance Director for several Israeli Television Channels.