The Internet of Things (IoT) has the potential to improve our lives through different services given the diversity of smart devices and their capabilities. But the large amounts of highly heterogeneous data captured by IoT devices typically require further processing to become useful information. The challenge is thus for IoT systems to determine which sensor data has to be captured/stored/processed/shared to, for instance, determine the occupancy of a specific office building or the spaces in which a potential COVID-19 exposure took place. This becomes even more challenging when IoT systems have to take into account privacy preferences of individuals. In this talk, I will introduce research efforts in the intersection of data management, knowledge representation & reasoning, and privacy to help IoT systems bridge the gap between the world of IoT devices and the world where people act.