Originally part of the Radio Liberty's Samizdat Archive, the Soviet Informal Press and Soviet Regional Press collection was considered to be the best and richest of its kind in the West. Although the Radio organized these publications into two series, it was sometimes not clear why a certain publication was placed in either of the series. The not very strict division is also suggested by the fact that the two series had one integrated printed catalog. Though the collections include a certain number of pre-Perestroika issues, they consist mainly of publications from the period between 1987 and 1992.
Printed catalog: Katalog russkoiazychnykh periodicheskikh izdanii, nakhodiashchikhsia v sobraniiakh neformal'noi i mestnoi pechati Issledovatel'skogo instituta RSE/RL, 1984-1993; Каталог русскоязычных периодических изданий, находящихся в собраниях неформальной и местной печати исследовательского института РСЕ/РС, 1984-1993.
In late 1989 a law called anti-censorship law was approved by the Soviet legislation allowing the publication of books and newspapers without government approval. As a result of the abolition of censorship, the number of publications issued by independent organizations and groups increased dramatically. For the most part, the 1.079 titles in the Informal Press can be considered as straight successors to Samizdat; the first independent publications of the Perestroika period document 20th century Soviet history, in particular dissent, artistic and religious movements. Following the Samizdat-era practice, these publications were smuggled out of the country to the West.