In the rapidly evolving landscape of modern infrastructure, smart buildings have become a cornerstone of sustainable and efficient urban development. Central to the functionality of these intelligent structures are advanced sensor technologies, notably Real Presence Sensors. These devices play a pivotal role in enhancing energy efficiency, occupant comfort, and automation. This article delves into the top five applications of Real Presence Sensors in smart buildings, highlighting their unique capabilities and benefits. Overview of Real Presence Sensors Real Presence Sensors, also known as True Presence Sensors or Real Presence Detectors, are advanced devices designed to detect the actual presence of individuals within a space, even in the absence of significant movement. Unlike traditional motion sensors that rely on detecting movement, these sensors can identify subtle physiological indicators such as micro-movements caused by breathing or heartbeat. This capability ensures higher accuracy in occupancy detection, reducing false positives and enhancing system integration within smart buildings.