Movement 21 (Bulgarian: Движение 21, romanized: Dvizhenie 21, D21) is a political party in Bulgaria established in 2011, led by Tatyana Doncheva.

In April 2010, Tatyana Doncheva, a former BSP deputy and member of the party's National Council, presented her new Movement 21 (D21) project, which she plans to set up as a civic association to be established as a non-governmental organization, and within a few months later became a political party.

[3] D21 joined the BSP – United Left electoral coalition in the run-up to the October 2024 election, but left the alliance in 2025 following the BSP leadership negotiating to join government with GERB.

[5] In the parliamentary elections in 2017, the party formed a coalition with Alternative for Bulgarian Revival (ABV), together receiving 54,412 actual votes, or 1.59% support, with 54.07% turnout.

In the 2019 European elections, the party received 4,141 actual votes, or 0.21% support, with 32.64% turnout.