[2] Tkachuk joined the Party of Communists of the Republic of Moldova (PCRM) in the early 2000s and became Domestic Policy Advisor to President Vladimir Voronin from 2001 to 2008.

[8] Tkachuk returned to politics in 2019, co-founding the Collective Action Party – Civic Congress alongside Iurie Muntean.

The party promotes left-wing, civil-labour oriented policies and has been moderate critical of both the pro-European and pro-Russian political agendas, focusing on issues such as social-market and responsible modernization.

In 2016, he established the public academic Library of Civilization, named after Marc Bloch, which started with a foundation of 50,000 books.

[18] Mark Tkachuk created a historical film series in collaboration with Newsmaker as part of the 2019 special project "Общий язык" (Common Language).

He established a new Faculty of Social Sciences at the High Anthropological School in collaboration with Manchester University and Shaninka, but, due to the political crisis stemming from oligarchic state capture and the subsequent impact of COVID-19, the project fell apart in its final stages.