The first significant post-Zhivkov act of the holdover (ninth) National Assembly was passage of twenty-one measures of constitutional reform. These measures included abolition of the article of the 1971 constitution giving the BCP sole right to govern. In April 1990, that National Assembly dissolved itself to make way for national election of a Grand National Assembly, charged with writing and ratifying a new constitution this was the first voluntary adjournment of that body since World War II.

In accordance with the provisions under which the 1990 parliamentary elections were held, after passing the new constitution in July 1991 the Grand National Assembly voted to dissolve itself and continue working as a normal parliament until election of the new body. Thus, in the second half of 1991 work would continue on critical legislation covering issues such as privatization, election procedures, and local government reform.

After the 1990 national elections, the National Assembly remained a weak legislative body, but for a new reason. No longer required to follow party orders precisely, representatives often were split quite evenly on reform issues. The majority BSP included reform and reactionary factions, and the 144 UDF members were a formidable opposition group. Unlike the brief assemblies of the Zhivkov era, the new body remained in session several days a week throughout the remainder of 1990 through mid-1991, struggling for compromise on reform legislation.

Data as of June 1992