Adolf Franz Karl Viktor Maria Loos[1] (German pronunciation: [ˈaːdɔlf ˈloːs]; 10 December 1870 – 23 August 1933) was an Austrian and Czechoslovak architect, influential European theorist, and a polemicist of modern architecture.

Loos attended multiple colleges also due to his poor academics and changing interests, which provided him a diverse skillset for architecture.

After leaving his last university, Loos visited America and was strongly impacted by the Chicago School of Architecture, inspired by "form follows function" philosophy of architect Louis Sullivan.

Loos then went on to write many literary pieces including the satirical piece The Story of a Poor Rich Man and his most popular manifesto, Ornament and Crime, which advocated for a lack or ornamentation, exemplified in his design of Looshaus, Vienna, in contrast to both the lavish decorations of the fin de siècle and the more modern aesthetic principles of the Vienna Secession.

Loos was born into a family of artisans on 10 December 1870 in Brno, in the Margraviate of Moravia region of the Austro-Hungarian Empire, today the eastern part of the Czech Republic.

Young Adolf Loos had inherited his father's hearing impairment and was significantly handicapped by it throughout his life, contributing to his solitary character.

[6] He then studied mechanics at the Royal and Imperial State Technical College in Liberec, but dropped to pursue building technology.

He then returned to mechanics again at State Crafts School in Brünn in 1889, and changed to architecture by studying at Dresden University of Technology from 1890 to 1893.

He could comprehend masonry and craftsman work and its impact on architecture, prompting recognition by many scholars based on his expertise.

[14] Living on the countryside made Loos admire America's rural culture, but he traveled to New York and Chicago to explore American metropolitan architecture.

Although noted for the lack of ornamentation on their exteriors, the interiors of many of Loos's buildings are finished with rich and expensive materials, notably stone, marble and wood, displaying natural patterns and textures in flat planes, executed in first rate craftsmanship.

[22] Loos collected sterling silver and high quality leather goods, which he noted for their plain yet luxurious appeal.

His admiration for the fashion and culture of England and America can be seen in his short-lived publication Das Andere, which ran for just two issues in 1903 and included advertisements for 'English' clothing.

From 1904 on, he was able to carry out big projects; the most notable was the so-called "Looshaus" (built from 1910 to 1912), originally for the Viennese tailor Goldman and Salatsch, for whom Loos had designed a store interior in 1898, and situated right across from the Habsburg city residence Hofburg Palace.

The facade was dominated by rectilinear window patterns and a lack of stucco decoration and awnings, which earned it the nickname "House without Eyebrows"; Emperor Franz Joseph I of Austria was said to have despised the modern building so much that he avoided leaving the Hofburg Palace through a main gate in its vicinity.

When the Austro-Hungarian Empire collapsed after World War I Loos was awarded Czechoslovakian citizenship by President Masaryk.

He taught at the Sorbonne and was contracted to build a house for Tristan Tzara, which was completed 1925 on Avenue Junot 15, Paris.

[35] Loos's body was taken to Vienna's Zentralfriedhof to rest among the great artists and musicians of the city, including Schoenberg, Altenberg and Kraus, some of his closest friends and associates.

His careful selection of materials, passion for craftsmanship and use of 'Raumplan'—the considered ordering and size of interior spaces based on function—are still admired.