Smart environment represents a world full of different sensors and smart devices seamlessly working together, making everyday living easier and more comfortable. According to Mark Weiser, a smart environment is "a physical world that is richly and invisibly interwoven with sensors, actuators, displays, and computational elements, embedded seamlessly in the everyday objects of our lives, and connected through a continuous network". To build a smart environment, interdisciplinary research in areas like wireless communication, speech and image processing and recognition, localization, sensors design, Radio Frequency Identification (RFID), Machine-to-Machine (M2M) communication and adaptive control is required. All these technologies, which are utilized in a variety of sensors, actuators, displays, and computational elements, are playing a fundamental role in enabling smart environments. This special issue on Smart Environment Technologies aims to report on recent advances in technologies, architectures, algorithms and protocols for smart environments with emphasis on real smart environment applications. Seven papers have been submitted and four of them have been recommended for publication based on standard reviewing process.