Mart (Martinus Adrianus) Stam (b. in 1899 in Purmerend, Netherlands—d. in 1986 in Goldach, Switzerland) was a Dutch architect, designer, and architectural theorist, and was involved in a number of principal events and organizations during the 1920s and 1930s.

Stam moved to Berlin in 1922 to work as a draftsman with Max Taut and Hans Poelzig among others. While in Berlin, Stam met El Lissitzky who introduced him to Constructivism. Inspired by the progressive and social outlook of this Russian movement Stam founded the avant-garde magazine ABC: Beiträge zum Bauen [ABC: Contributions on Building] together with Hans Schmidt, Hennes Mayer, and Emil Roth (1924–1928). The magazine focused on convincing readers about the social necessity for low-cost, well-designed, and functional houses, as well as the use of modern technologies. ABC also established connections with Asnova, the association of new architects in Moscow, and published the student work of Vkhutemas [School of Modern Architecture] in Moscow.