[1] The IBA followed two distinct strategies: "careful urban renewal" and "critical reconstruction.
"[1] With a budget of $1.2 billion, it was to house about 30,000 people in selected areas of West Berlin.
In 1979 Josef Paul Kleihues was appointed director of the IBA Neubau section by the Berlin Senate; Hardt Waltherr Hämer was director of the less-publicised Altbau[2] He organised the exhibition along two distinct themes: IBA Alt aimed to explore methods of "careful urban renewal" and IBA Neu for experimenting "critical reconstruction.
"[3] Kleihues invited many international architects from 10 countries[2] – including Gottfried Böhm, Mario Botta, Peter Eisenman, Vittorio Gregotti, John Hejduk, Herman Hertzberger, Hans Hollein, Arata Isozaki, Léon Krier, Rob Krier,[4] Charles Moore, Aldo Rossi and James Stirling[5] – to build in the following areas: the Prager Platz in Wilmersdorf as well as the Tegel, southern Tiergarten and southern Friedrichstadt districts.
Consequently, Time called the IBA "the most ambitious showcase of world architecture in this generation".