The recent technological development in wireless communication and mobile networks has led to many challenging problems that require new performance evaluation tools and methods to keep up with their rapid evolution and increasing complexity. As a result, performance modelling and evaluation has gained increasing importance. Whilst new applications and enhanced technologies are facilitating users' demands, researchers are facing challenges to provide models, tools and analytical techniques to aid with system design, prototyping, testing and performance evaluation.This special issue presents 10 high-quality papers from the first international workshop on Performance Analysis and Enhancement of Wireless Networks (PAEWN 2006) held in conjunction with the IEEE 20th International Conference on Advanced Information Networking and Applications (AINA 2006), Vienna, Austria and some related tracks. These papers were selected by the scientific program committee and extended and revised before undergoing further rigorous peer-review. The purpose of this workshop was to provide an international forum for researchers and industry practitioners to present their state-of-the-art research on performance analysis and evaluation studies in all aspects of wireless networking, and to exchange ideas and explore new avenues of collaborations. This workshop attracted a large number of quality submissions and the presentations generated very interesting discussions.This special issue has drawn upon the wide scope of challenging and timely issues related to wireless networks and the contents are built on experimental studies, analytical modelling, simulation studies, traffic modelling and applications for challenging issues.In the first paper [1], Speer and Chen discuss an important issue of energy conservation in datadriven wireless sensor networks (WSNs), where the system performs data sensing and retrieval as a response to users' queries at runtime. They argue that although the use of redundancy is desirable in terms of satisfying user queries to cope with sensor and transmission faults, it may adversely shorten the lifetime of the WSN. The authors analyse the effect of redundancy on the mean time to failure (MTTF) of a WSN in terms of the number of queries the system is able to answer correctly before it fails due to either sensor/transmission faults or energy depletion. In particular, they investigate the effect of redundancy on the MTTF of cluster-structured WSNs for energy conservations. Using a probability model, this paper demonstrates the existence of a tradeoff between redundancy and MTTF. Moreover, there exists an optimal level of redundancy that should be used by the system to maximize the MTTF.