(b Odessa, Russia, 23 June 1900; d Buenos Aires, 11 July 1967). Argentine architect. He studied architecture at the Istituto di Belle Arti in Rome, graduating in 1919. From 1922 he worked in Germany, gaining experience in building engineering and urban design, before moving to Argentina in 1928. He worked in Chile, Uruguay, Brazil, Venezuela, Guatemala and, from 1954 to 1957, in the USA, where he taught (1956) at Cornell University, Ithaca, NY. On his return to Argentina he was appointed Professor of Architectural Composition (1957–66) at the Universidad de Buenos Aires. Acosta was an early exponent of an approach to architecture through environmental design and engineering, which he promoted through his book Vivienda y clima (1937) and his ‘Helios’ buildings. These were based upon correct orientation, cross-ventilation, and the control of solar radiation by means of brises-soleil, with minimal mechanical intervention. Like the architects of the Modern Movement in Europe, he saw architecture as a social phenomenon and became dedicated to the provision of mass housing for rapidly growing urban populations. His early work included individual houses in Buenos Aires, for example the Casa Stern, Ramos Mejía (1939), the ‘Helios’ villa (1943) at La Falda, and others elsewhere in Argentina, at Rosario, Córdoba, Bahia Bianca and Bariloche. He also designed a psychiatric hospital (1942) at Santa Fé, but he is principally known for his multi-storey ‘Helios’ building: Departamentos de Figueroa Alcorta y Tagle (1942–3) and Co-operativa El Hogar Obrero workers’ housing (1954; with Fermin Bereterbide and A. Felici), Avenida Rivadavia y Riglos, Buenos Aires, a slim, 24-storey slab block on a two-storey podium. Acosta’s buildings are simple and astylar in the early Modern Movement genre, although expressive of the principles of solar control.