André Kuipers enjoyed looking out of the windows. On board the International Space Station, he had an unprecedented view of the earth. During his first journey into space, the Dutch astronaut observed "a tiny blue ball, shielded by the atmosphere that looks like a paper-thin, fluorescent layer" (Van Tongerloo, 2018). He also saw how precious our earth is, in particular when he looked at the deep and dark universe surrounding it. "I got a claustrophobic feeling from the view of my own planet. Then I realized: we only have that one blue ball. That is it." Other astronauts have made similar statements about changed perceptions of the planet after seeing it as a whole, free of national frontiers and impressed by its stunning beauty. The experience is so powerful that White (1998) termed it the "overview effect." That helps in realizing that natural resources are limited and action is needed to prevent expiry and all kinds of associated problems. This PhD thesis explores such action for the construction industry. This is no rocket science, but down-to-earth research. I systematically observed, analyzed and documented actual building projects and the issues that demolition and design managers face in reducing, reusing and recycling building materials. The latter had turned out to be no straightforward matter at all, as evidenced by a 'failed' project covered by several Dutch news articles (see e.g. Borren, 2016; Muis, 2016). In 2008, a "flexible and modular" school building was designed to accommodate a gymnasium in Amsterdam for five to ten years. The explicit ambition here was to relocate the building after that period, but in 2016 it was demolished in traditional ways. Deconstructing and rebuilding appeared too complex: the modular system was out of fashion already, a key supplier had gone bankrupt and important (de)constructability knowledge thereby also got lost. I consider such issues as information challenges here. The remarkable story inspired me to study other building projects accordingly. I integrated six studies in which I describe, explain and (sometimes) predict what is going on in those projects from a variety of perspectives (yet none of outer space, unfortunately). The integrated studies thereby provide some guidance for moving towards a circular built environment. Well ahead of his time, Boulding (1966) made a call for "the "spaceman" economy, in which the earth has become a single spaceship, without unlimited reservoirs of anything … and in which, therefore, man must find his place in a cyclical ecological system which is capable of continuous reproduction of material form." The seminal idea of a new economic system resonates today as the "circular economy," which is defined by the Ellen MacArthur Foundation (2013) as "an industrial system that is restorative or regenerative by intention and design." Policy-makers, business leaders and academics, particularly in Europe and China, have popularized the concept of a ii | Preface circular economy as an alternative for our current, wasteful "linear" econo...