Despite the name, current “green” architecture pays exclusive attention to being environmental friendly rather than being biophilic as well. Disregarding Nature in design is not just a matter of aesthetics but concerns also the quality of people’s lives. In order to achieve this, there is a need for a paradigm shift from “green” to “restorative” in order to really accomplish biophilic design. In the light of our experience in Human-Environment research we have devised the Biophilic Quality Index (BQI), a reliable instrument that allows us to calculate to what extent a building is biophilic. The rationale behind the BQI is simple: Biophilia is innate and affects attention through a proper operationalization of restorativeness and biophilic design is good when it enhances a restorative environment. The BQI can be used both as a guide to follow for a building-to-be, and as a rating system for an existing building, where the final score represents the space for improvement. The BQI will help architects integrate Nature in design and promote understanding that to plan restorative environments is not only an aesthetic need but a necessity for human’s efficient cognitive functioning.