Fiber optic sensing technology continues to be the subject of significant research endeavor investigating both the phenomena, which can be used in sensing, and the applications of techniques established within the laboratory. The ongoing interest is stimulated at the basic level by an ever-increasing portfolio of technologies through which light may be caused to interact with the physical, chemical, or biological conditions that surround it. In parallel, the applications oriented research, in areas from bioscience to structural monitoring to environmental assessment, has specifically highlighted one or more of the unique benefits which fiber sensor technology offers. These include the ability to operate over long interrogation distances, complete immunity to electromagnetic interference, intrinsic safety, and a very versatile range of measurand to lightwave transduction techniques. Further, as the technology enters application, the research becomes ever more interdisciplinary, embracing issues such as self-diagnosis and recalibration, sensor integration and data fusion, network architectures, packaging, system robustness, and long-term reliability. This special issue on distributed sensing, multiplexing, and sensor networking will contribute to encapsulating recent exciting developments in the incorporation of new transduction mechanisms to the guided wave format whilst in parallel covering the continually expanding world of field trials and application assessments. Optical fiber sensors continue to represent the core of the Special Issue, but the scope has been expanded to reflect growing new applications, new techniques, and material interactions of fiber optic technology especially in the life sciences and nanotechnology.The purpose of this special issue is to publish high-quality research papers as well as review articles addressing recent advances on distributed sensing in sensor networks. Original, high quality contributions that are not yet published or that are not currently under review by other journals or peer-reviewed conferences are sought.

Potential topics include, but are not limited to:

• Distributed sensing
• Time, frequency, and coherence domain reflectometry
• Optical fiber sensing
• Specialty optical fibers
• Optical sources and detectors
• Nonlinear optics for sensing
• Multiplexing topologies and theories
• Multiplexing techniques