RFID technology was originally envisioned to automate data collection in a supply chain. Over the last years, substantial progress has been made to integrate this technology into context-aware applications. A promising scenario is the use of passive RFID tags to implement home healthcare systems. Indeed, using RFID technology in such critical domain has grown in importance with the need of assisting people (e.g., elderly individuals and patients) in their everyday life. The deployment of the passive RFID technology is becoming more important with the standardization process through the Electronic Product Code (EPC) Class 1 Generation 2 tag standard, known as Gen2. As in many other emerging technologies, if countermeasures against attacks are not handled properly at the lowest levels of the architecture, security risks and privacy violations happen. In this book, we focus on the use of passive RFID devices, specifically the Gen2 tags. We deal with data leakage as a privacy issue in two levels: the first concerns the insecure radio communication interface linking RFID readers to tags. The second level focuses on the privacy issues in the middleware for filtering and collecting events