The state of the art on the architecture of former asylums presents multiple studies from different disciplines. As far as the architectural field is concerned, reference must be made to the historiography, composition, and restoration contributions. It is still unclear how well-informed society is about this type of heritage. Such large urban establishments, emblematic of the increasingly prominent dark heritage, are often subjects of simplistic narratives incapable of interpreting the tangible and intangible values. A congruent reuse perspective, starting from Foucault’s definition of heterotopic spaces and their various implications, requires profound readings of their architectural and functional history, as well as their spatial, typological, architectural, and material components. The purpose of the present contribution is to investigate the relationship between a specific asylum typology and the decommissioning process, seeking prolonged conditions throughout the “interim time” that elapsed between the ceased original function and the current state. This issue is inextricably linked to a process triggered after the enactment of the “Basaglia Law” in 1978, following which a complex and heterogeneous dismantling of the entire Italian asylum network was implemented. Assuming these conditions, the study focuses on the former Rizzeddu Psychiatric Hospital in Sassari, then expands to other national and international asylums to identify common features that could impact potential reuse processes. The investigation is pursued through various analyses and extended to the entire complex, with a specific contribution concerning the process of decommissioning and its relative implications. The goal is to raise awareness on the complexity of this topic, so that this heritage is effectively perceived as a witness of human history and therefore considered worthy of protection and transmission to the future.