Traditional Wireless Sensor Networks (WSNs) have tremendous applications, but their performance can be limited due to the limited processing and communication power of wireless sensor nodes. Cognitive Radio Sensor Networks: Applications, Architectures, and Challenges examines how wireless sensor nodes with cognitive radio capabilities can address these challenges and improve the spectrum utilization. This premier reference work presents a broader picture on the applications, architecture, challenges, and open research directions in the area of WSN research. It serves as a reference book for graduate students in courses on topics such as wireless sensor networks, cognitive radio networks, and emerging wireless technologies.