The leader known for their policy of glasnost in the Soviet Union was Mikhail Gorbachev. Glasnost, meaning "openness," was introduced in the mid-1980s as part of Gorbachev's reforms aimed at increasing transparency in government and encouraging freedom of expression. This policy allowed for greater dialogue regarding political and social issues, which was a significant departure from the repressive practices of previous Soviet leaders. Glasnost, alongside perestroika (restructuring), helped to catalyze a wave of political change, ultimately leading to the dissolution of the Soviet Union in 1991 and significant geopolitical shifts in Eastern Europe.