Fiber diffraction is used to determine the structures of filamentous assemblies at the molecular level.

FiberNet was established in 2004 by a network of fiber diffraction groups, and its mission is to coordinate activities in the USA and to develop biological fiber diffraction methods, particularly computational methods. This is done through a program of software development, and through a series of retreats and workshops. The network software is complementary to CCP13 software; together, they will eventually cover all aspects of biological fiber diffraction.

A major focus of activity is the cooperation between fiber diffractionists in the USA and others, particularly those in Britain. A second focus is the coordinated use of the BioCAT X-ray beamline facility at the Advanced Photon Source, Argonne National Laboratory. Network meetings include three types of activity: retreats that formalize a successful informal series held sporadically since 1989, workshops at BioCAT, and partial sponsorship of sessions organized by the fiber diffraction Special Interest Group of the American Crystallographic Association.

The network, formally known as Research Coordination Network: Fiber Diffraction from Biological Polymers and Assemblies, and informally as FiberNet, is supported by the National Science Foundation's Division of Molecular and Cellular Bioscience, through grant MCB-0234001.