In recent years, the Digital Twin (DT) has become an extremely popular technology in the Architecture, Engineering, Construction, and Operation industry (AECO). Its application benefits not only the design and construction phase of the building life cycle but also the operation and maintenance (O&M), supporting a more efficient facility management (FM). The DT most widespread applications are real-time monitoring, simulation, diagnosis, and performance prediction. DT allows to detect anomalies before they occur and make diagnosis, helping the decision-making process, and thanks to the presence of IoT, to control the conditions of the building, capturing current conditions such as temperature, humidity, noise, and occupancy. Supporting the sustainable transition of the built environment, the main outputs of DT implementation are the improvement of asset performance and building management. However, its application in FM is progressing slowly, largely due to the complexity of buildings, which involve various components. Given the projected scenario, the paper investigates the literature on the digital transformation in FM, identifying the advantages and disadvantages of digital technologies adoption and DT implementations. To outline the most common barriers that slow down this digital transformation in the FM market, the research develops a set of questions to collect opinions from a survey to FM operators. The study represents a preparatory investigation to compare academia and industry experiences on the introduction of digital technologies in the built environment during O&M.