Adam Borowski was an organiser and NSZZ "Solidarity" activist. In September 1980, he created the Workplace NSZZ "Solidarity" at the Miejskie Przedsiębiorstwo Robót Elektrycznych w Warszawie (Municipal Electrical Works Company in Warsaw). He later worked at the Komisja Interwencji i Mediacji NSZZ "Solidarność" Regionu Mazowsze (NSZZ "Solidarity" Intervention and Mediation Committee of the Mazovia Region). After martial law was imposed, he worked in the underground, where he organised multiple events, including the independent 1 May march in 1982, placing of the commemorative slab to the miners killed in the "Wujek" mine at the Victory Square in Warsaw, the release of Jan Narożniak, who was shot in May of 1982 by the MO, from the hospital. In July of 1982, Adam Borowski was arrested and sentenced by the Warsaw Military District Court to 6 years of deprivation of liberty.

He was released from prison on parole in July 1984. Next year, he joined Solidarność Walcząca (Fighting Solidarity) and organised its publishing activities in Warsaw. In 1989, he founded the "Volumen" Publishing House, which still exists today.

The "Solidarity: The Calendar" is the result of Adam Borowski's many years of work. The first entry concerns December 1975 and the sentencing of Stanisław Kruszyński to 10 months in prison for criticising the PRL political system in private letters. The second one concerns "Letter 59", issued by representatives of the cultural and scientific communities, concerning amendments to the PRL Constitution. According to the author, these moments started the formation of an anti-Communist opposition, which influenced the creation of NSZZ "Solidarity". The last entry in the "Solidarity: The Calendar" is 22 December 1990 - when Ryszard Kaczorowski, President of Poland-in-Exile- presented the newly-elected President of Poland Lech Wałęsa with the presidential insignia. This is the most extensive work of this type ever to be published. It is divided into three parts; December 1975-30 June 1980, 1 July 1980-12 December 1981, and 13 December 1981- December 1990, and presents the events, people, and places we all know, as well as those we sometimes forget about, or those we may have not even known about. Collecting all this information in one place is an extremely valuable source, which will undoubtedly be used by both Solidarity researchers and participants of the described events.