Josef Paul Kleihues has been regarded as one of Germany's most influential and prominent architects since the 1970s, who later also rose to international fame with his design of the Museum of Contemporary Art Chicago. He viewed himself not only as a designer and theoretician, but also as a teacher and instructor.

The projects he realised in the federal state of North Rhine-Westphalia take pride of place in his oeuvre. Although he initially set up shop in Berlin in 1962, he later opened a branch office in Dulmen-Rorup, where he worked on many projects, in particular in Westphalia and the Rhineland, beginning in the mid-1970s. In 1974, he became a professor at Dortmund University's newly established department of construction. His renown is based mainly on his Berlin projects. When he became director of planning responsible for new urban construction in the 1980s, Kleihues promoted the idea of 'critical reconstruction' with a focus on historical urban structures, urban construction typology, and local user interests, defying the contemporary modernist trends that were popular at that time.

While also giving a comprehensive overview of Kleihues's projects in North Rhine-Westphalia, this publication is the first to highlight the architect's extensive estate, most of which is held by Baukunstarchiv NRW.