The recent concern about the preservation of modern architecture as a cultural heritage raises important discussions about the principles that guide its preservation. Cultural heritage has been an important promoter of tourism and urban development actions. This relation is ambiguous. Although it is an important incentive to preserve buildings, it can also lead to distortions of the preservation guidelines. As regards modern architecture specifically, there are numerous projects that were demolished, while others were never built. These are essential elements for the comprehension of the modern discourse, recognized as a part of heritage. The recent construction of some of these projects, or supposed reconstructions, rely on falsification or “cloning,” by rebuilding the past through an idealized image, suppressing contradictions, accentuating an iconic character based on historiography, not facts. This practice contributes very little to the preservation of modern architecture, but it has shown to greatly influence urban policies.