(abridged version Bonas Essay) Van Hardeveld's oeuvre shows a remarkable dichotomy: church buildings and social housing. Most attention to date has gone to his experiments in standardized concrete construction of which pilot houses near Brussels and residential neighborhoods in Rotterdam, Den Bosch residential neighborhoods have been realized. His later public housing construction, is found almost exclusively in the expansion districts of Amsterdam. Van Hardeveld was born in Amsterdam in 1891. The basis for his later studies in architecture was education at the technical school, the evening drawing school and the industrial school. After which he found his first job in a carpentry business. He then worked as a supervisor and draftsman in architectural offices. He also worked in Belgium and France. He began his architectural training in Brussels at the Académie des Beaux Arts, but continued his education, presumably in connection with World War I, in the Netherlands. In the years 1914 to 1918, he trained at the Rijksacademie voor Beeldende Kunsten in Amsterdam. There, in his final year, he won the second prize in the Prix-de-Rome competition. Already in 1917 he established himself as an independent architect in Amsterdam. In 1923, he married the Frenchwoman Germaine Emilie Marie Bertin. The couple had two children Annicq (1924) and Yann Emile (1929). French was the language of communication in the family and the couple traveled frequently to the wife's native country. Possibly Van Hardeveld's preference for the use of vaults can be explained by his admiration for and knowledge of French Gothic architecture. He devoted himself within a Catholic context to the cultural exchange between his native country and that of his wife and was appointed Officer of the French Academy and was also awarded the Légion d'Honneur. In 1918, Van Hardeveld participated in the Prix de Rome. The brief was for "a representative building of the Netherlands in Rome with the aim of ensuring a dignified home for the arts and sciences, commerce and industry. Although Van Hardeveld's design, according to J.P. Mieras, was more interesting than that of his competitor H.P.J. de Vries, his floor plan had the disadvantage of being too complex. De Vries had taken the liberty of shaping the requested vestibule and main staircase as an open courtyard, thus providing a better solution for the southern climate. Peacock Jan Adrianus Pauw was born in Amsterdam on April 14, 1891,the son of Pieter Pauw (electrical engineer) and Cornelia Hendrika Tale. In November 1911 he married in Middelburg Cornelia Adriana Goethals, born in Middelburg on September 20, 1889 and died in Seattle, USA on October 31, 1966. Pauw died as the result of an automobile accident (Vancouver, Aug. 29, 1931). In the years 1918 to 1921, Van Hardeveld was associated with J.A. Pauw. He also occasionally worked with Pauw later on, such as for the competition building Coolsingel, corner Kruiskade (1929) Rotterdam. The earliest known project realized by the Pauw & Van Hardeveld firm was a complex of middle-class houses on Temsplein in Heerlen. Pauw had earlier won the competition for the planned library there. This design from 1917 still shows strong Berlagian features. The realized design, however, was designed in the style of the Amsterdam School. Possibly this can be explained by the influence of Van Hardeveld, whose name regularly appears in monument descriptions, wrongly or not, in connection with this building. On the other side of Temsplein, they built a number of middle-class houses in 1921 that appear 'modern' because of the flat roofs and colored bands. They also built a hotel-restaurant and the theater in this city. In 1920, a number of experimental concrete houses were built in Anderlecht near Brussels in the district of Het Rad. This was followed in 1921 by a similar experiment of 93 dwellings in the Strevelswijk district of Rotterdam known as "Isola I" after the name of the concrete building system. The second Isola project consisting of 396 houses and 13 stores was realized in the years 1922-1924 in Hillesluis and Strevelswijk. During the same time period, a working-class neighborhood consisting of 376 houses and 13 stores was built in Den Bosch. Further projects for standardized concrete construction in Betondorp and Karnemelksland in Rotterdam-Zuid (both 1922) were not realized. Fascinating are the designs that Van Hardeveld created with Pauw for several blocks of middle-class housing in Amsterdam and Groningen. These projects, residential houses with flat roofs were probably not realized. The results of experimental public housing construction in concrete were probably disappointing for Van Hardeveld, as they remained without imitation. Van Hardeveld's artistic milieu in the 1920s is somewhat evident from his contribution to the 1926 Building and Decorative Arts Exhibition in Utrecht. A newspaper report states: "Next Saturday afternoon the B.E.S.K. (Institution for Building and Decorative Arts) will be opened in Utrecht. Cooperation has been requested from a number of artists for a permanent international exhibition in the field of decorative and industrial art. Cooperation has been promised by W.M. Dudok, J.M. van Hardeveld, V. Huszar, Mrs. M. Kloos, W. van Leusden, J.J.P. Oud, Ir. S. van Ravesteyn, A.J. Westerman and Jan Wils. The exhibition includes exclusively "advanced-modern work, which is considered of significance for the future development of art, especially through purification of ineffective and meaningless detailing." A new period began after 1930, Van Hardeveld had already converted to the Catholic faith 10 years earlier. This revolution brought a change in his work, but has nothing to do with the abandonment of rational concrete construction principles, for as the above shows, this was a general trend in the Dutch construction world of the late 1920s. In those years he built a number of projects with a distinctly Catholic signature such as churches at Amstelveen (1932), Badhoevedorp (1936) and Dronrijp (rebuilding, 1938). The most famous project is the so-called small seminary at Apeldoorn (1934), which, however, was not unanimously praised at the time. A smaller nunnery in Groesbeek followed (1935). He also designed for clients with a Catholic background such as the fabric wholesaler Wyers (1929) and the department store Vroom & Dreesman (1944). Shortly before his death he designed the Roman Catholic church in Ede (1953). Before the war, Van Hardeveld also designed public housing for Catholic building societies. Of his early Amsterdam projects, the complex on Bataviastraat (1925; demolished) is of interest because it was published in contrast to his later projects. It appears pictured in the second installment of Modern Architecture in the Netherlands, on high-rise public housing. During the War, Van Hardeveld worked for Monumentenzorg. After the War, he realized mainly housing complexes in the expansion areas of Amsterdam. Evidently economic factors were decisive in construction here as elsewhere during this period. Additional functions: Rijksmonumentenzorg//1944;BNA/secretary/;BNA/vice-chairman/;St. Bernulphusgilde/board member/;RK-Staatspartij/advice member/;Stadenteraad Amsterdam/lid/;Commissie van advies voor de opleiding van Architecten aan de R.K. Leergangen, Tilburg/member/;Tijdschrift Bouwen en sieren/ editor-in-chief/;Katholieke Kunstkring 'De Violier'/member/;Schoonheidscommissie Amsterdam/member/1939 (about);World's Fair Paris/advisor Pavilion Religious Art/1937;Amitiés Catholiques Francaises/president/