255 Copyright © 2015, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Chapter 10 DOI: 10.4018/978-1-4666-6571-2.ch010 ABSTRACT Cognitive radio networks are a new technology based on which unlicensed users are allowed access to licensed spectrum under the condition that the interference perceived by licensed users is minimal. That means unlicensed users need to learn from environmental changes and to make appropriate decisions regarding the access to the radio channel. This is a process that can be done by unlicensed users in a cooperative or non-cooperative way. Whereas the non-cooperative algorithms are risky with regard to performance, the cooperative algorithms have the capability to provide better performance. This chapter shows a new fuzzy logic-based decision-making algorithm for channel selection. The underlying decision criterion considers statistics of licensed user channel occupancy as well as information about the competition level of unlicensed users. The theoretical studies indicate that the unlicensed users can obtain an efcient sharing of the available channels. Simulation results are reported to demonstrate the performance and efectiveness of the suggested algorithm. INTRODUCTION Today, one of the most active areas of research in Cognitive Radio (CR) is on Dynamic Spectrum Ac- cess (DSA), which refers to the method used to detect, to select and to access spectrum holes. Related to this, an important challenge for the research and industrial communities is to bridge the gap between the existent research results and the large-scale deployment of Cognitive Radio Networks (CRNs) (Akyildiz, On Fuzzy Logic-Based Channel Selection in Cognitive Radio Networks Yong Yao Blekinge Institute of Technology, Sweden Alexandru Popescu Blekinge Institute of Technology, Sweden Adrian Popescu Blekinge Institute of Technology, Sweden