In 1919 he became a member of the "Novembergruppe" and took the name Mies van der Rohe. Together with van Doesburg, Lissitzky and Richter he edited the magazine "G" in 1923. From his participation in G, he was strongly influenced by van Doesburg's neoplasticism. In those years, he worked on plans for two country houses, the Brick Chalet and the Mosler House. In 1924 he met the exhibition specialist and director of the Werkbund, Lilly Reich, with whom he partnered and worked until 1947.[3]​.

In 1926 he was chief architect of the German Werkbund exhibition. That same year he was appointed vice president of the Werkbund and together with Reich he carried out works of some magnitude, such as the Wolf House in Guben, all made of brick. He was director of the Weissenhof Dwelling exhibition in Stuttgart in 1927 while Reich was in charge of six of the exhibition halls. From 1927 to 1930 they built a villa in Krefeld for the silk manufacturer Hermann Lange, and in 1929 they were commissioned to direct the German Section and design the industrial exhibitions[4]​ and the German Pavilion "German Pavilion (Barcelona)") for the Barcelona International Exhibition "Barcelona International Exhibition (1929)"), for which they also designed the famous Barcelona chair,[5]​ made of chromed steel and leather. In 1930 they completed the Villa Tugendhat in Brno (now the Czech Republic).[6] He directed the Bauhaus in Dessau until it was closed in 1933 due to pressure to modify the school's study regime.

The rise of Nazism in Germany forced him to emigrate to the United States in 1937, where he was appointed director of the School of Architecture at the Illinois Institute of Technology in Chicago, which he later remodeled so that it was dedicated to teaching and research, and whose works were completed throughout the 1950s.

In 1938 he became director of the Department of Architecture at the Armor Institute, which years later joined the Lewis Institute to form the Illinois Institute of Technology. In 1940 he met Lora Marx, who accompanied him until his death. In 1944 he became a citizen of the United States. From 1945 to 1950 he built for Dr. Edith B. Farnsworth the house of the same name, the Farnsworth House in Plano "Plano (Illinois)"), Illinois.

Between 1948 and 1951 he realized his dream of building a glass skyscraper with the two towers of the Lake Shore Drive Apartments in Chicago, and later, the Commonwealth Promenade Apartments, also in the same city (1953-1956).

Among his most emblematic works from this period is the Seagram Building (1958), a 37-story glass and bronze skyscraper built in New York together with his disciple Philip Johnson.

In 1958 he retired from the Illinois Institute of Technology.

From 1962 to 1968 he built the New National Gallery in Berlin. It is a building dedicated to exhibitions of works of art, consisting of a large square room built entirely of glass and steel and located on an extensive terrace of granite slabs.

On August 17, 1969, he died in Chicago and left behind new canons for architecture under his much-publicized mottos "Less is more" and "God is in the details." He is considered one of the most important masters of modern architecture.

In 1919 he became a member of the "Novembergruppe" and took the name Mies van der Rohe. Together with van Doesburg, Lissitzky and Richter he edited the magazine "G" in 1923. From his participation in G, he was strongly influenced by van Doesburg's neoplasticism. In those years, he worked on plans for two country houses, the Brick Chalet and the Mosler House. In 1924 he met the exhibition specialist and director of the Werkbund, Lilly Reich, with whom he partnered and worked until 1947.[3]​.

In 1926 he was chief architect of the German Werkbund exhibition. That same year he was appointed vice president of the Werkbund and together with Reich he carried out works of some magnitude, such as the Wolf House in Guben, all made of brick. He was director of the Weissenhof Dwelling exhibition in Stuttgart in 1927 while Reich was in charge of six of the exhibition halls. From 1927 to 1930 they built a villa in Krefeld for the silk manufacturer Hermann Lange, and in 1929 they were commissioned to direct the German Section and design the industrial exhibitions[4]​ and the German Pavilion "German Pavilion (Barcelona)") for the Barcelona International Exhibition "Barcelona International Exhibition (1929)"), for which they also designed the famous Barcelona chair,[5]​ made of chromed steel and leather. In 1930 they completed the Villa Tugendhat in Brno (now the Czech Republic).[6] He directed the Bauhaus in Dessau until it was closed in 1933 due to pressure to modify the school's study regime.

The rise of Nazism in Germany forced him to emigrate to the United States in 1937, where he was appointed director of the School of Architecture at the Illinois Institute of Technology in Chicago, which he later remodeled so that it was dedicated to teaching and research, and whose works were completed throughout the 1950s.

In 1938 he became director of the Department of Architecture at the Armor Institute, which years later joined the Lewis Institute to form the Illinois Institute of Technology. In 1940 he met Lora Marx, who accompanied him until his death. In 1944 he became a citizen of the United States. From 1945 to 1950 he built for Dr. Edith B. Farnsworth the house of the same name, the Farnsworth House in Plano "Plano (Illinois)"), Illinois.

Between 1948 and 1951 he realized his dream of building a glass skyscraper with the two towers of the Lake Shore Drive Apartments in Chicago, and later, the Commonwealth Promenade Apartments, also in the same city (1953-1956).

Among his most emblematic works from this period is the Seagram Building (1958), a 37-story glass and bronze skyscraper built in New York together with his disciple Philip Johnson.

In 1958 he retired from the Illinois Institute of Technology.

From 1962 to 1968 he built the New National Gallery in Berlin. It is a building dedicated to exhibitions of works of art, consisting of a large square room built entirely of glass and steel and located on an extensive terrace of granite slabs.

On August 17, 1969, he died in Chicago and left behind new canons for architecture under his much-publicized mottos "Less is more" and "God is in the details." He is considered one of the most important masters of modern architecture.